Wave energy device with constricted tube and generator pod

ABSTRACT

A wave energy converter utilizes a flotation module that rises and falls with the passage of waves, a submerged tube containing a constriction which multiplies the speed of the water passing therethrough, a turbine (or other hydrokinetic apparatus) positioned so as to extract energy from the accelerated flow of water within and/or through the tube, and a submerged gas- or liquid-filled chamber housing one or more energy conversion components (e.g. generators, transformers, rectifiers, inverters). By providing a chamber in proximity to the turbine, generators can be placed in closer proximity to the turbine that turns them, and the shared shaft can be shorter than if the generators were placed in the buoy adjacent to the surface.

CROSS-REFERENCES TO RELATED APPLICATIONS

This is a continuation based on U.S. Ser. No. 17/231,776, filed on Apr.15, 2021; which is a continuation based on U.S. Ser. No. 16/544,726,filed on Aug. 19, 2019, U.S. Pat. No. 11,009,000, issue date of May 18,2021; which is a continuation based on U.S. Ser. No. 15/681,118, filedon Aug. 18, 2017, U.S. Pat. No. 10,358,820, issue date of Aug. 20, 2019;which claims priority from U.S. U.S. Ser. No. 62/377,679, filed Aug. 22,2016, and U.S. Ser. No. 62/383,579 filed Sep. 5, 2016, the contents ofwhich are fully incorporated by reference in their entirety.

BACKGROUND

Some embodiments of the disclosed apparatus are related to a class ofVenturi tube wave energy converters (“Venturi WECs”) that operate byusing the vertical (heave) component of wave motion to drive thevertical movement of an appropriately shaped tube suspended asignificant distance beneath the surface of the water, where water isrelatively unaffected by wave motion. The vertical movement of the tubethrough relatively still water causes water in the tube to transit fromone side of a constriction in the tube to the other, producing a flow ofwater through the constriction whose velocity is amplified relative tothe wave motion. By placing a hydrokinetic apparatus (e.g. a turbine) inor near the constriction and connecting this apparatus to conversionequipment (e.g. electrical generation equipment), wave energy can beefficiently converted to a useful form.

SUMMARY OF THE INVENTION

Disclosed is an apparatus that extracts energy from gravity wavespropagating across the surface of a body of water. The apparatus maycomprise of up to eight elements, as follows:

(1) A flotation module or buoy, intended to be located at the surface ofthe water during operation. The buoy moves up and down on passing waves.

(2) A rigid or non-rigid structural assembly, connected to the buoy,intended to descend beneath the buoy during operation. For instance, thestructural assembly might consist of struts, pillars, structurallattice, cable, or chain.

(3) A hollow tube, connected to the structural assembly, intended to besubmerged beneath the buoy in an approximately vertical orientationduring operation. The tube is open at its ends (the “mouths”) andcharacterized by at least one constriction where its internalcross-sectional area is reduced (the “throat” or “throats”). Thestructural assembly is to be of sufficient extent that the tube issuspended at a depth where water is little affected by wave motion(i.e., near or below the wave base). During operation, verticalmovements of the buoy are conveyed to the tube via the structuralassembly, causing the tube to move up and down. The vertical movement ofthe tube through relatively still water produces relative flows of waterwithin the tube. The relative velocity of these flows is amplified inthe throat or throats due to the reduced internal cross-sectional areathere.

(4) A submerged pod with fluid-impermeable walls, located within and/oradjacent to the tube, intended to contain and retain an internalatmosphere of gas and/or liquid of different composition from thesurrounding water, typically a non-conducting gas and/or liquid. The podis hermetically sealed or, if it has aperture(s), the apertures are sooriented as to allow the pod to retain its internal atmosphere byexploiting a difference in density between the internal atmosphere andthe surrounding water. For instance, an apertured pod might retain aninternal atmosphere of air by having aperture(s) oriented only down,retaining air by exploiting the buoyancy of air in water. The pod isintended to house one or more functional modules and to facilitate thefabrication of a submerged assembly of energy conversion equipment fromoff-the-shelf, ostensibly terrestrial components which would malfunctionif submerged unprotected. The pod may be modular and removable and/orreplaceable as a single unit.

(5) A hydrokinetic apparatus such as a turbine or flapping foil, locatedin or near a throat of the tube. Flows of water through such throatimpart kinetic energy to the hydrokinetic apparatus, causing it torotate, oscillate, flap, vibrate, or otherwise move.

(6) Located within the pod, conversion equipment for convertingmechanical or hydraulic energy into electrical power, and/or into a formof energy (e.g. mechanical, hydraulic, chemical, or electromagnetic)appropriate for an end-user, generator, transmission network, relay, orstorage system outside the pod. For instance, conversion equipment mightconsist of electrical generator(s), electrical alternator(s), electricalrectifier(s) or inverter(s), water pump(s), control system(s),computer(s), and/or similar.

(7) An inbound transmission system for transmitting mechanical and/orhydraulic energy from the hydrokinetic apparatus to the conversionequipment. For instance, the inbound transmission system might include ashaft, belt, chain, rod, crankshaft, hydraulic line, and/or magneticcoupling. The inbound transmission system might include one or morecomponents which traverse a wall of the pod via an aperture, or it mighttransmit mechanical energy to equipment inside the pod without the useof an aperture, for instance by shafts coupled using magneticallycoupled rotating discs.

(8) An outbound transmission system for transmitting energy and/orproducts from the conversion equipment to an end-user, generator,transmission network, relay, or storage system outside the pod, possiblyvia the buoy. For instance, such the outbound transmission system mightconsist of any number of electrical cables, hydraulic lines, conduits,substations, transformers, junctions, relays, generators, alternators,and/or similar.

Variations and extensions of the basic design are as follows:

(1) The interior of the tube might be provided with vanes intended todirect or condition flows of water as they move toward and/or away froma hydrokinetic apparatus.

(2) The exterior of the tube might be provided with fletching to promoteits smooth vertical movement through the water.

(3) The tube might be brought to its point of greatest constrictiongradually, so that the tube is a Venturi tube.

(4) The tube might be brought to its point(s) of greatest constrictionrapidly.

(5) The cross-sectional area of the tube might be constantly changingnear one or more of its mouths.

(6) The cross-sectional area of the tube might be approximately constantnear one or more of the mouths (forming cuffs).

(7) In regions where the cross-sectional area of the tube is changing,the change in diameter (or other cross-sectional width) might occur in alinear fashion.

(8) In regions where the cross-sectional area of the tube is changing,the change in diameter (or other cross-sectional width) might occur in anonlinear fashion.

(9) The pod might be pressurized so that its internal pressure is nearto, equal to, or greater than the pressure of the surrounding water.

(10) The pod might have no apertures (i.e. be hermetically sealed), orit might have one or more apertures.

(11) The pod might have baffles and/or other obstructions positionednear one or more of its apertures to impede displacement of the internalatmosphere by water.

(12) Replenishment equipment might be provided inside or outside the pod(for instance on or in the buoy) to continuously or periodicallyreplenish the pod's internal atmosphere. For instance, replenishmentequipment might include a pump/compressor and conduit to conduct air tothe pod from the surface. Or, replenishment equipment might includeequipment that generates the internal atmosphere locally, for instanceequipment that generates hydrogen gas by electrolysis of the surroundingwater. Replenishment equipment might include compressors, pumps, hoses,pipes, filters, membranes, gas or fluid separation equipment,electrolysis equipment, dehumidifiers, and/or similar.

(13) Conditioning equipment might be provided inside or outside the pod(for instance on or in the buoy), or might be embedded in the pod'swalls, to condition the internal atmosphere. For instance, conditioningequipment might include coolers, heaters, heat pumps, condensers,dehumidifiers, fans, filters, membranes, gas or fluid separationequipment, and/or similar.

(14) Mechanical bearings might be located within the pod to facilitatethe rotation or oscillation of one or more components of the inboundtransmission system, conversion equipment, and/or hydrokineticapparatus.

The prior art contemplates designs of Venturi WECs in which electricalgeneration equipment is located in one of two locations: (1) at thesurface (e.g., in the buoy), or (2) underwater (e.g. adjacent to thetube). Each of these the designs contemplated in the prior art hassignificant disadvantages:

(1) Placing electrical generation equipment in the buoy requires anextensive assembly for transmitting mechanical energy from thehydrokinetic apparatus to the buoy, e.g., a shaft which can exceed 50meters in length. Such an assembly is costly, unwieldy, and subject tosignificant mechanical losses; and

(2) Placing electrical generation equipment underwater has historicallyrequired the use of underwater generators using special shaft seals.Such generators are costly, difficult to procure, limited in size andfeatures, prone to seal failure, and susceptible to corrosion.Electrical connections must be well insulated or short-circuits willoccur.

Furthermore, in prior designs, bearings for the turbine and shaft havebeen located underwater. Underwater bearings are susceptible tocorrosion and biofouling.

The disclosed apparatus ameliorates the foregoing disadvantages by usinga submerged chamber, or “pod”, to maintain an internal atmosphere ofdifferent composition from the surrounding water in a location adjacentto the tube and hydrokinetic apparatus. This design has severaladvantages:

(1) The pod and its internal atmosphere provide protection for sensitiveconversion equipment by preventing contact with water;

(2) The pod and its internal atmosphere likewise provide protection forsensitive parts of the inbound transmission system, such as bearings, bypreventing contact with water;

(3) The pod precludes the need for an extensive and unwieldy mechanicalassembly for transmitting mechanical energy to conversion equipmentlocated at the surface;

(4) The pod precludes the need for costly and failure-prone conversionequipment specifically designed for underwater applications;

(5) The pod promotes the use of low-cost, commodity equipment byproviding an environment in which the equipment may operate as if in aterrestrial application;

(6) The pod promotes modularity by locating assortments of relatedequipment in a single design unit which may be manufactured, installed,and/or replaced at once, an important consideration when deployingand/or maintaining devices in violent marine conditions; and

(7) The pod promotes flexibility and extensibility by providing aplatform for ad hoc combinations of conversion and transmissionequipment.

Terminology

baffle—a wall or barrier that is used to control and/or retard the flowand/or splashing of water up to and/or on to components, e.g.generators, located within a pod.

bi-directional blades—turbine blades that move, e.g. as about a radialaxis coincident with the longitudinal axis of a turbine of which theblade is a part, so as to propel the turbine in a consistent and/orconstant direction of rotation regardless of the direction from whichfluid flows across, over, and/or through, the turbine. In other words,bi-directional turbine blades move away from a flow so as to divert flowand thereby impart rotational kinetic energy to the turbine to whichthey are directly and/or indirectly attached. By moving away from a flowregardless of the direction from which it flows, bi-directional turbineblades adapt to any flow at least in part parallel to the longitudinaland/or rotational axis of the turbine so as to provide an unchangingdirection of tangential thrust to the turbine.

bi-directional turbine—a turbine that rotates in a single directionregardless of the direction from which fluids flows across, over, and/orthrough, the turbine, when said flow is at least partially parallel tothe longitudinal and/or rotational axis of the turbine.

constriction—a reduction in the cross-sectional area of a channel,lumen, and/or tube, with respect to planes normal to the longitudinaland/or length-wise axis of the channel, lumen, and/or tube.

converging cone—that portion of a constricted tube, especially of a“Venturi tube,” in which the normal cross-sectional area decreases withrespect to the direction of a fluid's flow, often at a constant rate ofreduction with respect to distance along a longitudinal tube axis. In aconstricted tube and/or Venturi tube possessing two portions with normalcross-sectional areas that increase as they move away from the throat,the definition and/or designation of which “constricting” portion is a“converging cone” and which is a “diverging cone” is determined by thedirection of the fluid's flow. Fluid enters the constricted portion viaa “converging cone” and exits the throat and the constricted portion viaa “diverging cone.”

cuff—an end portion of a tube characterized by an approximately, if notentirely, constant normal cross-sectional area.

diverging cone—that portion of a constricted tube, especially of a“Venturi tube,” in which the normal cross-sectional area increases withrespect to the direction of a fluid's flow, often at a constant rate ofincrease with respect to distance along a longitudinal tube axis.

heave—the up-and-down component of a wave's motion.

heave point absorber—a point-absorber that extracts energy primarily, ifnot entirely, from the heave of the waves that pass through, around,under, and/or over, it.

generator—a device which produces electricity, electrical power,electrical voltage, and/or electrical current. Unless specificallyclarified, a reference to a “generator” may refer to a generator properand/or to an alternator, and/or to any other electricity-generateddevice and/or apparatus.

normal cross-sectional area a cross—sectional area of a channel, lumen,and/or tube, with respect to at least one plane that is normal to atleast one longitudinal and/or length-wise axis of the channel, lumen,and/or tube.

pod—a chamber that is at least partially submerged in water and is atleast partially filled with a fluid (such as a gas) of a differentcomposition from the water in which it is submerged. A “pod” is anextensible chamber that can house one or more functional modules and/orcomponents, and which facilitates the fabrication of a submergedenergy-conversion assembly from off-the-shelf, and ostensiblyterrestrial, products, which, without the non- or less-corrosiveenvironment provided within a pod might be expected to quickly corrodeand/or fail.

point-absorber—a category of devices used for the extraction of energyfrom waves moving across the surface of a body of water. These devicesgenerate the same, or approximately the same, amount of power inresponse to the passage of waves of a particular height and periodregardless of the geographical and/or relative direction from which suchwaves approach and pass under, over, around, and/or through the devices.

throat—that point or those points along the length of, and/or thatportion, or those portions, of, a constricted tube wherein thecross-sectional area or areas is or are equal to the locally or globallyminimum cross-sectional area(s) characteristic of the tube.

transverse plane—The transverse plane (also called the horizontal plane,axial plane, or transaxial plane) is an imaginary plane that divides anembodiment, an embodiment's buoy, or an embodiment's tube, (depending onthe context or the qualifying description) into superior and inferior,i.e. into upper and lower, parts.

longitudinal cross-sectional area—a cross-sectional area of a channel,lumen, and/or tube, with respect to at least one plane that passesthrough, and/or is in a radial relation to, at least one longitudinaland/or length-wise axis of the channel, lumen, and/or tube.

Many of the figures, illustrations, descriptions and claims are madewith respect to objects floating on the sea and/or anchored to theseafloor. However, this disclosure and all such figures, illustrations,descriptions and claims are intended to apply with equal force to anyother body of water, e.g. a lake, overlying any other type of non-fluidsurface, e.g. the bottom surface of a lake. The scope of thisdisclosure, all of its elements, and all of its claims, are intended toinclude embodiments designed for use on, and/or actually used on, anybody of water.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic view of a first preferred embodiment of thepresent invention;

FIG. 1B is a cross-sectional view of the embodiment of FIG. 1A;

FIG. 2A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 2B is a cross-sectional view of the embodiment of FIG. 2A;

FIG. 3A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 3B is a cross-sectional view of the embodiment of FIG. 3A;

FIG. 4 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 5 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 6 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 7 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 8 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 9 is a schematic view of a another preferred embodiment of thepresent invention;

FIG. 10 is a schematic view and cross-sectional view of an alternatepreferred embodiment of the present invention;

FIG. 11 is a schematic view and cross-sectional view of an alternatepreferred embodiment of the present invention;

FIG. 12 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 13 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 14A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 14B is a cross-sectional view of the embodiment of FIG. 14A;

FIG. 15 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 16A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 16B is a second schematic view of the embodiment of FIG. 16A;

FIG. 16C is a third schematic view of the embodiment of FIG. 16A;

FIG. 17A-C are schematic views of an alternate preferred embodiment ofthe present invention;

FIG. 18A-I are schematic views of an alternate preferred embodiment ofthe present invention;

FIG. 19 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 20 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 21 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 22 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 23 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 24 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 25 is an enlarged, perspective view of a turbine used with thepresent invention;

FIG. 26 is an enlarged, perspective view of another turbine used withthe present invention;

FIG. 27 is an enlarged, perspective view of another turbine used withthe present invention;

FIG. 28 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 29 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 30 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 31 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 32 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 33 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 34 is a schematic view of a pod of the present invention;

FIG. 35A is a schematic view of another pod of the present invention;

FIG. 35B is a cross-sectional view of the embodiment of FIG. 35A;

FIG. 36 is a schematic view of yet another pod of the present invention;

FIG. 37 is a schematic view of another pod of the present invention;

FIG. 38 is an enlarged, sectional view of another pod of the presentinvention;

FIG. 39 is a schematic view of another pod of the present invention;

FIG. 40 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 41 is a schematic cross-sectional view of an alternate preferredembodiment of the present invention;

FIG. 42 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 43 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 44 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 45 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 46A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 46B is a cross-sectional view of an alternate preferred embodimentof FIG. 46A;

FIG. 47A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 47B is a cross-sectional view of an alternate preferred embodimentof FIG. 47A;

FIG. 48 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 49 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 50A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 50B is a cross-sectional view of the embodiment of FIG. 50A;

FIG. 51 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 52A is a cross-sectional view of a pod of the present invention;

FIG. 52B is a top view of the magnetic coupler of the pod of FIG. 52A;

FIG. 53 is a cross-sectional view and side view of another pod of thepresent invention;

FIG. 54 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 55 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 56 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 57 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 58 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 59 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 60 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 61 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 62 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 63 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 64 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 65 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 66 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 67A is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 67B is a cross sectional view of a pod used with the embodiment ofFIG. 67A;

FIG. 67C is a graph of rpm versus depth for the embodiment of FIG. 67A;

FIG. 68 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 69 is a schematic view of a series of wave energy converters;

FIG. 70 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 71 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 72 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 73 is a schematic view of an alternate preferred embodiment of thepresent invention;

FIG. 74 is a schematic view of an alternate preferred embodiment of thepresent invention; and

FIG. 75 is a schematic view of yet another alternate preferredembodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

For a fuller understanding of the nature and objects of the disclosure,reference should be made to the following detailed description, taken inconnection with the accompanying drawings, in which:

FIG. 1A is an illustration of an embodiment of the invention disclosedherein. An embodiment 100 floats adjacent to the surface 101 of a bodyof water having a wavebase 102. As waves lift, and let fall, theembodiment, a tube 119, rigidly attached to a buoy 100 by means of aplurality of rigid struts, e.g. 107 and 121, and possessing aconstriction 115, is driven up-and-down through the still watersadjacent to and/or below the wavebase 102.

As the tube 119 is accelerated up and down by the heave of the wavemotion at the surface the inertia of the water inside the tube causesthat water to resist the tube's accelerations. The pressure of the waterin the leading end of the tube (i.e. the top portion of the tube whenthe embodiment is rising, and the bottom portion of the tube when theembodiment is falling) increases as the water in that portion of thetube resists the compression of the accelerating tube. And, conversely,and in complementary fashion, the pressure of the water in the trailingend of the tube (i.e. the bottom portion of the tube when the embodimentis rising, and the top portion of the tube when the embodiment isfalling) decreases as the water in that portion of the tube resists thesuction of the accelerating tube.

Amplified pressure on one side of the tube's throat, and a partialvacuum on the other side, drives water through the throat and throughany turbine (or other hydrokinetic apparatus) therein. Sincehydrokinetic turbines extract power primarily, if not entirely, from thespeed and/or kinetic energy of the water passing therethrough, the useof a constricted tube to convert inertia-induced pressure changes intoadditional water speed allows for a more efficient extraction of energyfrom a fluid flowing through an accelerating tube, such as through thisembodiment's heave-accelerated tube.

The pressure-amplified flow of water through the throat of theembodiment's tube 119 imparts rotational kinetic energy to the turbine118 therein. This rotation kinetic energy is communicated via a shaft111 and 110 (same shaft) to a generator 109 positioned inside an“air-filled” chamber or “pod” 108.

Tube and Pod Cross-Sectional Shapes and Struts

The embodiment illustrated in FIG. 1A contains and/or utilizes aconstricted tube 119 in which all of the normal cross-sectional areasare approximately, if not perfectly, circular in shape. In thisembodiment, the normal cross-sectional shape of the pod 108 is alsoapproximately, if not perfectly, circular. For example, the normalcross-sectional view at the right side of the figure illustrates thestereotypical circular cross-sectional shapes of both the tube 113 andthe pod 108.

A cross-sectional illustration is located at FIG. 1B. Thecross-sectional perspective is taken along the plane signified as 122 inFIG. 1A. The cross-sectional perspective shows that this embodimentutilizes eight struts, e.g. 107 and 121, to connect the submerged tubeto the surface buoy.

Pod

The pod 108 of the embodiment illustrated in FIG. 1A, has a “pointy”upper “cap” (or top portion) and a frusto-conical lower cap. Note thatthe bottom of the pod 108 is above the tube 119, and above and “outside”the normal cross-sectional plane that includes the upper tube mouth 119.Shaft 110-111 penetrates the pod 108 wall via an aperture in the bottomcap.

Turbine

The embodiment illustrated in FIG. 1A contains and/or utilizes a rigidturbine 118 that rotates in one direction when water flows through thetube and turbine in an upward direction, and rotates in the oppositedirection when water flows through the tube and turbine in a downwarddirection.

Tube Vs Wavebase

The submerged constricted tube of the embodiment illustrated in FIG. 1Ais positioned within the body of water 101 such that its upper mouth 119is adjacent to the wavebase 102.

Cuffs

The constricted tube 119 has five sections defined by their geometries.The tube 119 has: 1) an upper cylindrical portion 113 wherein the normalcross-sectional area is relatively, though not necessarily perfectly,constant; 2) an upper frusto-conical portion 114 within which the normalcross-sectional area is decreasing, with respect to increasing depth, atan approximately, though not necessarily perfectly, constant rate; 3) acentral “throat” portion 115 wherein the normal cross-sectional area isrelatively, though not necessarily perfectly, constant and isapproximately, though not necessarily, the smallest normalcross-sectional area within the tube 119; 4) a lower frusto-conicalportion 116 within which the normal cross-sectional area is increasing,with respect to increasing depth, at an approximately, though notnecessarily perfectly, constant rate; and, 5) a lower cylindricalportion 117 wherein the normal cross-sectional area is relatively,though not necessarily perfectly, constant.

Symmetry

The tube 119 exhibits, and/or is characterized by, at least anapproximate bi-lateral symmetry with respect to a transverse planethrough the midpoint of the tube, and with respect to a transverse planethrough the throat (or point or portion of minimal normalcross-sectional area).

Modules

One or more tubes, cables and/or wires, 112 connect the interior of thepod 108, and/or components positioned therein, e.g. 109, with theinterior of the buoy 100, and/or with other components, e.g. 103-104,positioned therein.

In one embodiment illustrated in FIG. 1A, module 103 inside the buoyprovides electrical signals, via wires located within cables 105 and112, to an alternator 109 located in the pod. Other wires located withincables 105 and 112, return to module 103 the electrical power generatedby the alternator 109 as a consequence of turns of the shaft 110-111 andthe energizing electrical signals provided to the alternator.

In one embodiment illustrated in FIG. 1A, any electrical power returnedfrom the alternator, and/or “generated”, is then “conditioned” and/orconverted (e.g. from three-phase alternating current to direct current)so as to prepare it for transmission to and through a subsea power cableto an onshore substation and/or for direct utilization and/or for directtransmission to and through an electrical power grid.

In one embodiment illustrated in FIG. 1A, a generator 109, generateselectrical power in response to the turning of shaft 110-111. That poweris returned to module 103 via wires in cables 112 and 105 wherein it isconditioned and/or converted and thereafter utilized and/or transmitted,directly and/or indirectly, to a consumer of electrical power, e.g. agrid, a motor, etc.

In one embodiment illustrated in FIG. 1A, module 104 inside the buoyprovides compressed air via one or more tubes located within cables 106and 112. The compressed air is communicated to an entry port and/oraperture adjacent to the bottom of the pod 108 via cable 112. The airadded to the pod displaces, and forces out, any water that may belocated at the bottom of the pod, e.g. at the aperture where the shaftenters the pod.

In one embodiment illustrated in FIG. 1A, the “pod gas supply module”104 extracts nitrogen from compressed air, and then communicates thenitrogen (absent any oxygen) to the pod. In the presence of nitrogen,and, more importantly, in the absence of oxygen, the generator and/orother components inside the pod will experience a reduced rate ofcorrosion.

In one embodiment illustrated in FIG. 1A, the “pod gas supply module”104 dehumidifies the compressed air prior to transmitting it to the pod.A steady influx of such dehumidified air reduces the rate ofmoisture-accelerated corrosion, especially if the dehumidified “air” isactually free of oxygen.

Venturi Tube

In one embodiment illustrated in FIG. 1A, the constricted tube 119 is a“Venturi tube” in which the geometric proportions of the tube causewater to flow through it over a significant range of speeds without thegeneration of significant turbulence. This embodiment's Venturi tube isa bi-directional adaptation of a Venturi tube, in which the rate atwhich the normal cross-sectional area of the tube changes with respectto the longitudinal axis of the tube is sufficiently small so as toreduce the occurrence of turbulence in the fluid flowing out of thetube's throat regardless of whether the fluid is flowing up or downthrough the tube. (I.e. in a “traditional” Venturi tube, fluid flow isuni-directional and the rate at which the normal cross-sectional area ofthe tube changes with respect to the longitudinal axis of the tube canbe greater in that portion of the tube in which the fluid flows towardthe throat, than in that portion of the tube in which the fluid flowspast and/or away from the throat.)

In one embodiment illustrated in FIG. 1A, the constricted tube 119 isnot a “Venturi tube”. The rate at which the normal cross-sectional areathrough which fluid may flow through the tube changes is too greatand/or sudden, at least with respect to one position along the length ofthe tube, and/or at least one portion of the tube, for fluid to flow ina laminar fashion across the range of fluid-flow speeds typical of theembodiment's operation, therefore and/or thereby resulting in theproduction, instigation, and/or formation of at least some turbulencewithin the flow with respect to at least one speed, and/or range ofspeeds, of fluid flow.

FIG. 2A is an illustration of an embodiment of the invention disclosedherein.

Tube and Pod Cross-Sectional Shapes and Struts

Unlike the embodiments discussed with respect to FIG. 1A, the embodiment200 illustrated in FIG. 2A contains a “tube” 219 and/or channel definedand/or constructed with flat panels, e.g. 214 and 216. The normalcross-sectional view of FIG. 2B illustrates the square normalcross-sections characteristic of this embodiment. The submerged tube 219characteristic of this embodiment is rigidly connected to the buoy 200by four rigid struts, e.g. 207, 224, and 221.

Despite the rectangular shape of the tube, the pod 208 has a circularnormal cross-section (as illustrated in FIG. 2B).

Pod

The pod 208 of the embodiment illustrated in FIG. 2A, has a“hemi-spherical” upper “cap” (or top portion) and a flat, truncatedlower cap. Note that the bottom of the pod 208 is above the tube 219,and above and “outside” the normal cross-sectional plane that includesthe upper tube mouth 219. Shaft 210-211 penetrates the pod 208 wall viaan aperture in the bottom cap.

Turbine

The embodiment illustrated in FIG. 2A contains and/or utilizes a turbine218 that possesses a single row of blades that rotate through therotational plane to either of two operational orientations and/orpositions. The “bi-directional” blades cause this turbine to rotate inthe same constant direction regardless of whether water flows throughthe tube and turbine in an upward or a downward direction.

Cuffs

The constricted tube 219 has three sections defined by their geometries.The tube 219 has: 1) an upper frusto-conical section 214 within whichthe normal cross-sectional area is decreasing, with respect toincreasing depth, at an approximately, though not necessarily perfectly,constant rate; 2) a central “throat” portion (surrounding turbine 218)wherein the normal cross-sectional area is relatively, though notnecessarily perfectly, constant and is approximately, though notnecessarily, the smallest normal cross-sectional area within the tube219; and, 3) a frusto-conical section 216 within which the normalcross-sectional area is increasing, with respect to increasing depth, atan approximately, though not necessarily perfectly, constant rate.

Modules

In one embodiment illustrated in FIG. 2A, a module 203 provideselectrical signals, via one or more wires in cables 205 and 212, andcontrol of at least one alternator 209 positioned in the gas-filled pod208. One or more additional wires in cables 205 and 212 return generatedelectrical power to module 203 where it is conditioned and/or convertedso as to manifest electrical properties compatible with an intendedconsumer of the power and/or its transmission via one or more powercables to a land-based substation and/or power grid.

In one embodiment illustrated in FIG. 2A, a source 204A of pressurizedgas is released via a controlling valve 204B into a tube and/or line206, and which is incorporated within cable 212, and is therebyadministered into the interior of the pod 208 chamber. The gas maydisplace any water collected adjacent to the aperture through which theshaft 211 enters the pod. In one embodiment the gas is compressed air.In another it is relatively pure nitrogen gas. And in another it isdehumidified. In another embodiment, it is dehumidified nitrogen gas.

In one embodiment illustrated in FIG. 2A, the source 204A is a source ofoil and/or another petroleum product, which is released via acontrolling valve 204B. Due to its negative specific weight (i.e. itsbuoyant) the oil floats at the top of the pod 208 and pushes out anywater collected adjacent to the shaft's aperture.

Venturi Tube

In one embodiment illustrated in FIG. 2A, the constricted tube 219 is a“Venturi tube” and is characterized by substantially, if notconsistently, laminar flow. In another embodiment, the constricted tube219 is not a “Venturi tube” and manifests some, if not substantialdegrees of, turbulence.

FIG. 3A is an illustration of an embodiment of the invention disclosedherein.

Tube and Pod Cross-Sectional Shapes and Struts

Unlike the embodiments illustrated in FIGS. 1A and 2A, the embodiment300 illustrated in FIG. 3A contains a “tube” 319 and/or channel definedand/or constructed with flat panels, e.g. 314, arrayed, connected,and/or joined, in a hexagonal normal cross-sectional pattern. The normalcross-sectional view at FIG. 3B illustrates the hexagonal normalcross-sections characteristic of this embodiment. The submerged tube 319characteristic of this embodiment is rigidly connected to the buoy 300by six rigid struts, e.g. 307, which themselves have square normalcross-sectional shapes.

Pod

The pod 308 of the embodiment illustrated in FIG. 3A, has a “flat” upperand lower “caps” (or end portions). Note that the bottom of the pod 308is relatively far above the tube 319, and is closer to the bottom of thebuoy 300 than it is to the upper tube mouth 319. Shaft 310-311penetrates the pod 308 wall via an aperture in the bottom cap.

Turbine

The embodiment illustrated in FIG. 3A contains and/or utilizes a turbine318 that possesses two rows of blades, each blade of which rotatesthrough the rotational plane of its respective row of blades to eitherof two operational orientations and/or positions. These “bi-directional”blades cause this turbine to rotate in the same constant directionregardless of whether water flows through the tube and turbine in anupward or a downward direction.

Tube Vs Wavebase

The submerged constricted tube of the embodiment illustrated in FIG. 3Ais positioned within the body of water 301 such that its upper mouth 319is above the wavebase 102, and its lower mouth 320 is below the wavebase102.

Cuffs

The constricted tube 319 has a “smooth” and/or “hourglass” verticalcross-sectional shape. Starting at either mouth, the normalcross-sectional area of the tube decreases at a relatively small ratewith increasing proximity to the center of the tube. The rate ofreduction in the normal cross-sectional area of the tube increases at agrowing rate with further increases in proximity to the center of thetube. And, finally, near the center of the tube, the rate of reductionin the normal cross-sectional area of the tube slows, and finally stops,when it reaches an approximate, if not actual, minimal normalcross-sectional area at and/or near its center.

Modules

In one embodiment illustrated in FIG. 3A, a passive pump 304, driven bythe surge of waves, draws air 328 in through a tube 326, one end ofwhich is open to the ambient air, and transmits it under pressure intothe interior chamber of the pod 308 via tube 312B. Anelectrically-powered mechanical pump 324 provides an alternate and/orredundant supply of pressurized air (and/or nitrogen extracted and/orfiltered from the air) into the pod 308 chamber via tubes 325 and 312A.

Module 303 conditions power generated by the generator and/or alternator309 and transmitted to the module via wire(s) contained in cables 312Aand 305. In one embodiment, 309 is an alternator and, in addition toconditioning generated electrical power, module 303 also issueselectrical signals that control and/or energize the alternator, e.g.varying the current through the alternator's field coils so as tomaintain a constant shaft rpm.

Venturi Tube

In one embodiment illustrated in FIG. 3A, the constricted tube 319 is a“Venturi tube” and is characterized by substantially, if notconsistently, laminar flow. In another embodiment, the constricted tube319 is not a “Venturi tube” and manifests some, if not substantialdegrees of, turbulence.

FIG. 4 is an illustration of an embodiment of the invention disclosedherein.

Pod

The pod 408 of the embodiment illustrated in FIG. 4 , has a“hemi-spherical” upper “cap” (or top portion) and a frusto-conical lowercap. Note that the bottom of the pod 408 is within the tube 419, and thepod crosses the normal cross-sectional plane that includes the uppertube mouth 419. Shaft 411 penetrates the pod 408 wall via an aperture inthe bottom cap.

Cuffs

The constricted tube 419 has four sections defined by their geometries.The tube 419 has: 1) an upper cylindrical portion 413 wherein the normalcross-sectional area is relatively, though not necessarily perfectly,constant; 2) a frusto-conical section 414 within which the normalcross-sectional area is decreasing, with respect to increasing depth, atan approximately, though not necessarily perfectly, constant rate; 3) afrusto-conical section 416 within which the normal cross-sectional areais increasing, with respect to increasing depth, at an approximately,though not necessarily perfectly, constant rate; and, 4) a lowercylindrical portion 417 wherein the normal cross-sectional area isrelatively, though not necessarily perfectly, constant.

Throat

Unlike the embodiments illustrated in FIGS. 1-3 , the tube 419 does nothave an extensive “throat”. The junction between adjacent frusto-conicaltube portions 414 and 416 constitutes the “throat” with respect to thisembodiment.

Symmetry

Unlike the embodiments illustrated in FIGS. 1-3 , the tube 419 does notexhibit, nor is it characterized by, bi-lateral symmetry with respect toa transverse plane through the midpoint of the tube, nor with respect toa transverse plane through the throat (or point or portion of minimalnormal cross-sectional area).

Note that the upper frusto-conical portion 414 of the tube 419 is longerthan the corresponding lower frusto-conical portion 416. Note also thatthe normal cross-sectional area of the upper frusto-conical portion 414diminishes more slowly, with respect to increasing proximity to thetube's throat, than does the adjacent lower frusto-conical portion 416.

Venturi Tube

In the embodiment illustrated in FIG. 4 , the constricted tube 419constitutes, and exhibits fluid dynamic behavior consistent with, a“Venturi tube” when descending toward an approaching wave trough.However, when rising toward an approaching wave crest, the constrictedtube 419 does not exhibit fluid dynamic behavior consistent with that ofa “Venturi tube.”

The reason for this inconsistent behavior is that as it falls, waterenters the tube 419 through its lower mouth 420 and then flows through arelatively “aggressive” converging cone 416, which is capable ofproducing exclusively laminar fluid flow when accelerating fluid flowspeed. The water then exits the throat and flows through a lessaggressive diverging cone 414, which is also capable of producingexclusively laminar fluid flow when accelerating fluid flow speed.

However, when the flow is reversed, and water enters the upper mouth 419and flows out through a relatively short and “aggressive” diverging cone416, turbulence may result. A proper “Venturi tube” is designed,fabricated, and utilized, so as to cause water exiting the throat toflow through a relatively long and relatively unaggressive divergingcone in which the normal cross-sectional area increases relativelyslowly. Such a gradual deceleration of the accelerated flow is requiredto avoid substantial turbulence.

FIG. 5 is an illustration of an embodiment of the invention disclosedherein.

Pod

The pod 508 of the embodiment illustrated in FIG. 5 , has“hemi-spherical” upper and lower “caps” (or end portions). Shaft 511penetrates the pod 508 wall via an aperture in the bottom cap.

Tube Vs Wavebase

The submerged constricted tube of the embodiment illustrated in FIG. 5is positioned within the body of water 501 such that its upper mouth 519is below the wavebase 502.

Cuffs

The constricted tube 519 has three sections defined by their geometries.The tube 519 has: 1) an upper cylindrical portion 513 wherein the normalcross-sectional area is relatively, though not necessarily perfectly,constant; 2) a central “hourglass-shaped” portion 514 in which thenormal cross-sectional area is relatively minimal at the approximatecenter, and increases at varying, perhaps even discontinuous, rates withincreasing distance from the center; and, 4) a lower cylindrical portion517 wherein the normal cross-sectional area is relatively, though notnecessarily perfectly, constant.

Symmetry

Unlike the embodiments illustrated in FIGS. 1-3 , the tube 519 does notexhibit, nor is it characterized by, bi-lateral symmetry with respect toa transverse plane through the midpoint of the tube, nor with respect toa transverse plane through the throat (or point or portion of minimalnormal cross-sectional area).

Note that the upper “cuff” portion 513 of the tube 519 is longer thanthe corresponding lower cuff portion 517.

Note also that the upper portion 514 of the “hourglass” portion of thetube 519 is longer than the corresponding lower portion 516 of the“hourglass” portion of the tube 519. Note also that the normalcross-sectional area of the upper frusto-conical portion 514 diminishesmore slowly, with respect to increasing proximity to the tube's throat,than does the adjacent lower frusto-conical portion 516.

Venturi Tube

In the embodiment illustrated in FIG. 5 (for reasons discussed inrelation to FIG. 4 ), the constricted tube 519 constitutes, and exhibitsfluid dynamic behavior consistent with, a “Venturi tube” when descendingtoward an approaching wave trough. However, when rising toward anapproaching wave crest, the constricted tube 519 does not exhibit fluiddynamic behavior consistent with that of a “Venturi tube.”

FIG. 6 is an illustration of an embodiment of the invention disclosedherein.

Pod

The pod 608 of the embodiment illustrated in FIG. 6 , has“frusto-conical” upper and lower “caps” (or end portions). However,unlike the embodiments illustrated in FIGS. 1-5 , shaft 611 penetratesthe pod 608 wall via an aperture at the bottom of a tubular extensionprojected from the bottom cap.

Turbine

The embodiment illustrated in FIG. 6 contains and/or utilizes a rigidturbine 618 that rotates in one direction when water flows through thetube and turbine in an upward direction, and rotates in the oppositedirection when water flows through the tube and turbine in a downwarddirection.

Cuffs

The constricted tube 619 has four sections defined by their geometries.The tube 619 has: 1) an upper cylindrical portion 613 wherein the normalcross-sectional area is relatively, though not necessarily perfectly,constant; 2) a frusto-conical section 614 within which the normalcross-sectional area is decreasing, with respect to increasing depth, atan approximately, though not necessarily perfectly, constant rate; 3) acentral “throat” portion 615 wherein the normal cross-sectional area isrelatively, though not necessarily perfectly, constant and isapproximately, though not necessarily, the smallest normalcross-sectional area within the tube 619; and, 4) a frusto-conicalsection 416 within which the normal cross-sectional area is increasing,with respect to increasing depth, at an approximately, though notnecessarily perfectly, constant rate.

Symmetry

Unlike the embodiments illustrated in FIGS. 1-3 , the tube 619 does notexhibit, nor is it characterized by, bi-lateral symmetry with respect toa transverse plane through the midpoint of the tube, nor with respect toa transverse plane through the throat (or point or portion of minimalnormal cross-sectional area).

This embodiment has an upper 613, but not a lower, cuff.

Note also that the upper frusto-conical portion 614 of the tube 619 isshorter than the corresponding lower frusto-conical portion 616 of thetube 619. Note also that the normal cross-sectional area of the upperfrusto-conical portion 614 diminishes more quickly, with respect toincreasing proximity to the tube's throat, than does the complementarylower frusto-conical portion 616.

Venturi Tube

In the embodiment illustrated in FIG. 5 (for reasons generally discussedin relation to FIG. 4 , and contrary to the embodiment illustrated anddiscussed in relation to FIGS. 4 and 5 ), the constricted tube 619constitutes, and exhibits fluid dynamic behavior consistent with, a“Venturi tube” when ascending toward an approaching wave crest. However,when descending toward an approaching wave trough, the constricted tube619 does not exhibit fluid dynamic behavior consistent with that of a“Venturi tube.”

FIG. 7 is an illustration of an embodiment of the invention disclosedherein.

Pod

The pod 708 of the embodiment illustrated in FIG. 6 , has an ellipsoidalshape.

Turbine

The embodiment illustrated in FIG. 7 contains and/or utilizes a rigidturbine 718 that rotates in one direction when water flows through thetube and turbine in an upward direction, and rotates in the oppositedirection when water flows through the tube and turbine in a downwarddirection.

Cuffs

The constricted tube 719 has three sections defined by their geometries.The tube 719 has: 1) an upper frusto-conical section 714 within whichthe normal cross-sectional area is decreasing, with respect toincreasing depth, at an approximately, though not necessarily perfectly,constant rate; 2) a frusto-conical section 716 within which the normalcross-sectional area is increasing, with respect to increasing depth, atan approximately, though not necessarily perfectly, constant rate; and,3) a lower cylindrical portion 717 wherein the normal cross-sectionalarea is relatively, though not necessarily perfectly, constant.

Throat

Unlike the embodiments illustrated in FIGS. 1-3 , the tube 719 does nothave an extensive “throat”. The junction between adjacent frusto-conicaltube portions 714 and 716 constitutes the “throat” with respect to thisembodiment.

Symmetry

Unlike the embodiments illustrated in FIGS. 1-3 , the tube 619 does notexhibit, nor is it characterized by, bi-lateral symmetry with respect toa transverse plane through the midpoint of the tube, nor with respect toa transverse plane through the throat (or point or portion of minimalnormal cross-sectional area).

This embodiment has a lower 717, but not an upper, cuff.

Note also that the lower frusto-conical portion 716 of the tube 719 isshorter than the corresponding upper frusto-conical portion 714 of thetube 719. Note also that the normal cross-sectional area of the lowerfrusto-conical portion 716 diminishes more quickly, with respect toincreasing proximity to the tube's throat, than does the complementaryupper frusto-conical portion 714.

Venturi Tube

In the embodiment illustrated in FIG. 7 (for reasons discussed inrelation to FIG. 4 ), the constricted tube 719 constitutes, and exhibitsfluid dynamic behavior consistent with, a “Venturi tube” when descendingtoward an approaching wave trough. However, when rising toward anapproaching wave crest, the constricted tube 719 does not exhibit fluiddynamic behavior consistent with that of a “Venturi tube.”

FIG. 8 is an illustration of an embodiment of the invention disclosedherein.

Pod

The pod 808 of the embodiment illustrated in FIG. 8 , has“hemi-spherical” upper and lower “caps” (or end portions). Note that thebottom of the pod 808 is above the tube 819, and above and “outside” thenormal cross-sectional plane that includes the upper tube mouth 819.Shaft 811 penetrates the pod 808 wall via an aperture in the bottom cap.

Turbine

The embodiment illustrated in FIG. 8 contains and/or utilizes a turbine818 that possesses a single row of blades that rotate through therotational plane to either of two operational orientations and/orpositions. The “bi-directional” blades cause this turbine to rotate inthe same constant direction regardless of whether water flows throughthe tube and turbine in an upward or a downward direction.

Cuffs

The constricted tube 819 has five sections defined by their geometries.The tube 819 has: 1) an upper frusto-conical portion 813 wherein thenormal cross-sectional area is decreasing, with respect to increasingdepth, at an approximately, though not necessarily perfectly, constantrate; 2) an adjacent frusto-conical portion 814 within which the normalcross-sectional area is decreasing, with respect to increasing depth, atan approximately, though not necessarily perfectly, constant rate, andis decreasing more quickly than upper frusto-conical portion; 3) acentral “throat” portion 815 wherein the normal cross-sectional area isrelatively, though not necessarily perfectly, constant and isapproximately, though not necessarily, the smallest normalcross-sectional area within the tube 819; 4) a frusto-conical section816 within which the normal cross-sectional area is increasing, withrespect to increasing depth, at an approximately, though not necessarilyperfectly, constant rate; and, 5) a lower frusto-conical portion 817wherein the normal cross-sectional area is relatively, though notnecessarily perfectly, constant, and is decreasing more slowly thanadjacent frusto-conical portion.

Symmetry

The tube 819 exhibits, and/or is characterized by, at least anapproximate bi-lateral symmetry with respect to a transverse planethrough the midpoint of the tube, and with respect to a transverse planethrough the throat (or point or portion of minimal normalcross-sectional area).

Venturi Tube

In one embodiment illustrated in FIG. 8 , the constricted tube 819 is,and exhibits fluid-dynamical behavior consistent with, a “Venturi tube”.In another embodiment, the constricted tube 819 is not a “Venturi tube”.

FIG. 9 is an illustration of an embodiment of the invention disclosedherein.

Turbine

The embodiment illustrated in FIG. 9 contains and/or utilizes a rigidturbine 1714 that rotates in one direction when water flows through thetube and turbine in an upward direction, and rotates in the oppositedirection when water flows through the tube and turbine in a downwarddirection.

Cuffs

The constricted tube 1708 has four sections defined by their geometries.The tube 1708 has: 1) an upper cylindrical portion 1709 wherein thenormal cross-sectional area is relatively, though not necessarilyperfectly, constant; 2) a first frusto-conical portion 1710 within whichthe normal cross-sectional area is decreasing relatively slowly, withrespect to increasing depth, and decreasing at an approximately, thoughnot necessarily perfectly, constant rate; 3) a second frusto-conicalportion 1711 within which the normal cross-sectional area is decreasingrelatively quickly, with respect to increasing depth, and decreasing atan approximately, though not necessarily perfectly, constant rate; and,4) a “throat” portion 1712 wherein the normal cross-sectional area isrelatively, though not necessarily perfectly, constant and isapproximately, though not necessarily, the smallest normalcross-sectional area within the tube.

Throat

Unlike the prior embodiments illustrated in FIGS. 1-8 , the embodimentillustrated in FIG. 9 has its throat at the lower end of the tube, andthe bottom perimeter of the throat defines and “is” the lower mouth ofthe tube 1708.

Symmetry

The tube 1708 does not exhibit, nor is it characterized by, bi-lateralsymmetry with respect to a transverse plane through the midpoint of thetube, nor with respect to a transverse plane through the throat (orpoint or portion of minimal normal cross-sectional area).

The tube 1708 accepts a relatively “wide” stream 1715 of water intoand/or through its upper mouth 1708 when rising in response to anapproaching wave. However, it accepts a relatively “narrow” stream 1716of water into and/or through its lower mouth when falling in response toa departing wave. This embodiment will manifest significant drag, andgenerate a relatively significant amount of power, with respect toupward accelerations in response to approaching wave crests. Bycontrast, it will manifest a relatively minimal amount of drag, andgenerate a relatively minimal amount of, if any, power, with respect todownward accelerations in response to approaching wave troughs.

Venturi Tube

The constricted tube 1708 is not a “Venturi tube”.

FIG. 10 is an illustration of an embodiment of the invention disclosedherein.

Turbine

The embodiment illustrated in FIG. 10 contains and/or utilizes a turbine1808 that is positioned such that an upper portion of the turbine, aswell as the shaft to which it is attached, are “above” a normalcross-sectional plane that includes the upper tube mouth 1808. A lowerportion of the turbine is “below” a normal cross-sectional plane thatincludes the upper tube mouth 1808. The turbine 1808 straddles the uppermouth of the constricted tube 1809-1810.

Cuffs

The constricted tube 1809-1810 has two sections and/or portions withrespect to their geometries. The tube 1809-1810 has: 1) an upperfrusto-conical portion 1809 within which the normal cross-sectional areais increasing with respect to increasing depth and/or distance down thelongitudinal axis of the tube, and increasing at an approximately,though not necessarily perfectly, constant rate; and, 2) a lower portion1810 wherein the normal cross-sectional area is relatively, though notnecessarily perfectly, constant.

In one embodiment illustrated in FIG. 10 , the normal cross-sectionalshapes of the tube at various points along its length are circular. Inanother embodiment, they are elliptical. In another, they are square. Inanother, they are hexagonal. In another octagonal. In anotherrectangular . . . . The scope of the present disclosure extends toconstricted tubes of all normal cross-sectional shapes, and/or of anycombination of such shapes. It also extends to constricted tubes of allvertical cross-sectional shapes. It extends to constricted tubespossessing any combination of tube portions in which the normalcross-sectional areas of those portions are approximately, if notabsolutely, increasing, decreasing, or constant; and/or to any suchcombination of such portions, and to any and all orderings of suchportions.

Throat

With respect to the embodiment illustrated in FIG. 10 , the “throat”, ortube portion possessing a normal cross-sectional area no greater thanany other normal cross-sectional area of the tube, is found at, and isco-located with, the upper mouth 1808.

Symmetry

The tube 1808 does not exhibit, nor is it characterized by, bi-lateralsymmetry with respect to a transverse plane through the midpoint of thetube, nor with respect to a transverse plane through the throat (orpoint or portion of minimal normal cross-sectional area).

The tube 1808 accepts a relatively “wide” stream 1813 of water intoand/or through its lower mouth 1811 when falling in response to adeparting wave. However, it accepts a relatively “narrow” stream 1812 ofwater into and/or through its upper mouth when rising in response to anapproaching wave. This embodiment will manifest significant drag, andgenerate a relatively significant amount of power, with respect todownward accelerations in response to approaching wave troughs. Bycontrast, it will manifest a relatively minimal amount of drag, andgenerate a relatively minimal amount of, if any, power, with respect toupward accelerations in response to approaching wave crests.

Venturi Tube

The constricted tube 1809-1810 is not a “Venturi tube”.

FIG. 11 is an illustration of an embodiment of the invention disclosedherein.

Pod

The embodiment illustrated in FIG. 11 contains and/or utilizes a pod1912 that is positioned outside an upward and/or downward projection ofthe tube, and is located to the side of the tube 1904 adjacent to thelower tube mouth 1910. The longitudinal axis of the pod, and/or theshaft 1914 therein, is not coincident with the longitudinal axis of thetube 1904, nor with the shaft 1911 therein.

The generator 1913 is rotationally connected to the turbine 1907 bymeans of three shaft segments 1911, 1916 and 1914. These three shaftsegments communicate rotational kinetic energy from the turbine 1907 tothe generator 1913 by means of interfacing, complementary, and/orinterlocked, pairs of bevel gears 1915 and 1917.

An advantage to positioning the pod 1912 outside of upward and/ordownward projection of the tube is that the pod will not disrupt theflow of water into and/or out of the tube as the device rises and fallsin response to the passing of waves beneath its buoy 1900.

Turbine

The embodiment illustrated in FIG. 11 contains and/or utilizes abi-directional turbine 1907 that possesses a single row of“bi-directional” blades.

Cuffs

The constricted tube 1904 has five sections defined by their geometries.The tube 1904 has: 1) an upper cylindrical portion 1905 wherein thenormal cross-sectional area is relatively, though not necessarilyperfectly, constant; 2) an upper frusto-conical portion 1906 withinwhich the normal cross-sectional area is decreasing, with respect toincreasing depth, at an approximately, though not necessarily perfectly,constant rate; 3) a central “throat” portion adjacent to the turbine1907 wherein the normal cross-sectional area is relatively, though notnecessarily perfectly, constant and is approximately, though notnecessarily, the smallest normal cross-sectional area within the tube;4) a lower frusto-conical portion 1908 within which the normalcross-sectional area is increasing, with respect to increasing depth, atan approximately, though not necessarily perfectly, constant rate; and,5) a lower cylindrical portion 1909 wherein the normal cross-sectionalarea is relatively, though not necessarily perfectly, constant.

Symmetry

The tube 1904 does not exhibit, nor is it characterized by, bi-lateralsymmetry with respect to a transverse plane through the midpoint of thetube, nor with respect to a transverse plane through the throat (orpoint or portion of minimal normal cross-sectional area).

Note that the upper “cuff” portion 1905 of the tube 1904 is longer thanthe corresponding lower cuff portion 1909.

Venturi Tube

In one embodiment illustrated in FIG. 11 , the constricted tube 1904 is,and exhibits fluid-dynamical behavior consistent with, a “Venturi tube”.In another embodiment, the constricted tube 1904 is not a “Venturitube”.

FIG. 12 is an illustration of an embodiment of the invention disclosedherein.

A pod 2004 is positioned above the upper mouth 2005 of the constrictedtube 2007-2011. At least one generator within the pod 2004 is directlyand/or indirectly rotatably connected to at least one turbine within theconstricted tube 2007-2011 by a connection that includes at least shaft2006. A “cage” 2003 protects the pod 2004 from collisions and from theingress of debris from above the tube. The tube 2007-2011 and/or itscage 2003 are connected to a buoy 2000, floating adjacent to a surface2001 of a body of water, by means of a plurality of flexible connectors2002, e.g. chains.

FIG. 13 is an illustration of an embodiment of the invention disclosedherein.

A pod 2105 is positioned above the upper mouth 2106 of the constrictedtube 2107-2112. A “cage” 2103-2104 protects the pod 2105 from collisionsand from the ingress of debris from above the tube. The tube 2107-2112and/or its cage 2103-2104 are connected to a buoy 2100, floatingadjacent to a surface 2101 of a body of water, by means of a singleflexible connector 2102, e.g. by a single chain.

FIG. 14A and FIG. 14B are illustrations of an embodiment of theinvention disclosed herein.

A pod 2207 and 2216 is positioned inside (shown as though through atransparent tube wall for the purpose of illustration and explanation) aconstricted tube 2206, 2210, and 2212-2214. The constricted tube is anintegral extension of a perforated tube 2204 that extends from the buoy2200, floating adjacent to a surface 2201 of a body of water. The upperperforated portion 2204 of the tube allows ambient water to move, e.g.2202 and 2217, freely in and out of the tube through holes e.g. 2203 and2218. The lower, non-perforated portion(s) 2206, 2208, 2210, and2212-2214, of the tube laterally constrain the water therein, and, inresponse to vertical accelerations of the embodiment driven by therising and falling of the surface 2201 of the water as a consequence ofthe passage of waves, the inertia of the laterally constrained watercauses it to push against, though, and past, the turbine 2211 positionedin the throat 2212 of the tube.

FIG. 15 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein.

A pod 2312 is positioned inside a tube 2309 that is connected to,attached to, and/or an integral extension of, a buoy 2300, floatingadjacent to a surface 2301 of a body of water.

This tube 2309 is open to the body of water 2301 by means of a mouth2320 at it bottom. As the device 2300 is driven up and down by passingwaves, the effective “depth” (i.e. pressure) of the water inside thetube is inconsistent with the actual depth (i.e. pressure) of thewave-driven surface 2301 of the ambient water. The wave-inducedalternating increase and decrease in the pressure of the water at thedepth 2318 of the lower tube mouth 2320 drives 2310 the water inside thetube to reach and/or match a comparable pressure, and to raise itssurface 2308 to the oscillating surface 2301 of the ambient water, andthereby reduce the discrepancy 2306 in the heights of the internal 2308and external 2301 surfaces of the waters.

The inertia of the water inside the tube, and the constriction 2316 ofthe tube, result in a latency between changes in the effective depth2318 of the lower mouth 2320 of the tube with respect to the ambientwater, and the effective depth (2318-2307) of the lower mouth 2320 ofthe tube with respect to the water inside the tube.

This latency, and/or phase differential, between the verticaloscillations of the device 2300 and the movements of water within thetube drives the turbine 2315 in the throat of the tube 2309, therebydirectly and/or indirectly communicating rotational kinetic energy fromthe turbine 2315 to at least one generator within the pod 2312 by meansthat include shaft 2313.

Furthermore, the tube 2309 of the embodiment illustrated in FIG. 15 isconnected to the atmosphere at its upper end by means of a turbinecharacteristic of, and/or functionally consistent with, that of an“oscillating water column” (OWC). Atmospheric gases are able to move2303 into and out from a hollow chamber 2305 within the buoy 2300 andupper portion of the connected tube 2309. As the surface 2308 of thewater inside the tube 2309 moves 2310 up and down, the air within theupper portion 2305 of the tube and buoy moves 2304 up and down as well.This causes air to alternately move 2303 into, and out of, the chamber2305, thereby turning and/or energizing the OWC-compatible wind turbine2302.

This embodiment utilizes a relative vertical oscillation of the waterinside its tube 2309 to drive both a water-driven turbine 2315 in thethroat of the constricted portion of the tube, and an air-driven turbine2302 interposed between the upper mouth of the tube and the ambientatmosphere.

Because the tube 2309 of this embodiment has no perforations, and onlycommunicates with the water outside the tube by means of a single mouth2320 at its lower end, this embodiment facilitates the use of chemicalagents, added to the water (e.g. at its surface 2308) inside the tube,to retard the growth of organisms that might otherwise lead to“bio-fouling.” Since such added chemicals would not quickly nor readilydiffuse out of the water inside the tube, their use would be practicaland efficient, and would be expected to have a minimal, if any, negativeimpact on the environment and/or ecosystem(s) sharing the body of waterwith the device 2300.

FIGS. 16A-16C are cross-sectional-perspective illustrations of anembodiment of the invention disclosed herein.

FIG. 16A illustrates a pod 908 is positioned above an upper mouth 919 ofa constricted tube. A turbine 918 in the throat 915 of the tube 919 isspun by water that moves through the tube and relative to the tube inresponse to the tube's wave-driven vertical accelerations. As the tubeaccelerates up and down in response to wave movement, the inertia of thewater inside the tube inhibits its ability to move in synchrony with thetube. This results in a “relative” flow of water, i.e. from the tube'sperspective, while in reality it is the tube that is moving and thewater is substantially at rest.

The water that “flows” up and down through the tube in response to thedevice's 900 wave-induced oscillations is accelerated by the tube'sconstriction. At or near a point 915 of maximal acceleration, a turbine918 extracts kinetic energy from the water. The resulting rotationalkinetic energy is communicated from the turbine 918 to an attached shaft911. That shaft is connected, via coupler 934, to another complementaryshaft 933 which directly and/or indirectly communicates the turbine'srotational kinetic energy to at least one generator, alternator, waterpump, and/or other mechanism that converts the rotational kinetic energyinto a useful byproduct.

A hole 936 that passes through the buoy 900 is of a sufficient width,shape, and/or character, so as to permit the passage of the pod 908 fromone vertical side of the buoy 900 to the other and/or back again.

FIG. 16B illustrates the separation of the pod 908 from the turbine 918to which it is indirectly connected during the embodiment's operation.The coupling element 934 has separated into upper 934B and lower 934Aportions, thus permitting the vertical ascent 937 of the pod 908.

FIG. 16C illustrates the egress of the pod 908 from the hole 936 withinthe buoy, and thus the separation of the pod 908 from the rest of theembodiment's components.

FIGS. 16A-16C illustrate one of the many methods by which the poddisclosed herein can be removed from an embodiment, e.g. formaintenance, repair, and/or replacement, and (by viewing the figures inreverse, i.e. FIGS. 16C through 16A, how a pod can be reconnected to anembodiment.

This feature and/or mechanism provides the useful ability to access,remove, and/or replace, an otherwise and/or nominally submerged pod 908from the safety and/or convenience of a ship, and/or other locationadjacent to, and/or above, the surface 901 of the body of water on whichthe device operates.

FIGS. 17A-17C are cross-sectional-perspective illustrations of anembodiment of the invention disclosed herein.

As was illustrated and discussed in FIGS. 16A-16C, FIGS. 17A-17C providefor, and/or facilitate, the removal, maintenance, repair, and/orreplacement, of an embodiment's 1000 pod 1008. In the embodimentsillustrated in FIGS. 17A-17C, the pod 1008 is removed while stillconnected to its associated turbine 1018. A coupler and/or positionalfixture 1030 remains within the tube 1019 and provides positional androtational stability to the rotating turbine 1018 and its connectedshaft 1011.

FIG. 17A shows the pod 1008, the turbine 1018, and the shaft 1011 thatconnects the turbine to the at least one generator within the pod 1008,in their operational positions and/or configuration.

FIG. 17B illustrates the separation of the pod-shaft-turbine assembly(1008, 1011, and 1018) from the embodiment through its lifting 1037 anddisengagement from the receiving and/or stabilization fixture 1030.

FIG. 17C illustrates the removal of the pod-shaft-turbine assembly(1008, 1011, and 1018) from the embodiment through its lifting 1037 andits passage through the hole 1036 in the buoy 1000.

A pod-shaft-turbine assembly (1008, 1011, and 1018) is added to, andreconnected with, an embodiment through a reversal of the stepsillustrated, i.e. FIGS. 17C through 17A.

FIGS. 18A-18I are cross-sectional-perspective illustrations of anembodiment of the invention disclosed herein.

Like the embodiments illustrated in FIGS. 17A-17C, and FIGS. 18A-18C,the embodiments illustrated in FIGS. 18A-18I, provide for the removal ofa pod. However, the embodiment illustrated in FIGS. 18A-18I provide forthe removal of the pod, the shaft, and the turbine, without the need fora fixture (e.g. 1030 of FIGS. 17A-17C) to be left permanently attachedto the tube, thereby blocking the tube even after the removal of thepod, shaft, and turbine.

The embodiment illustrated in FIG. 18A includes a pod 2414 that isattached to, and positioned by means of, a structure 2415 (e.g. a plateand/or planar structure) hereafter referred to as two or more “radialpod fins”. This structure 2415 is, in turn, positionally constrained byand within two or more slots, e.g. 2404, in which the structure is ableto “slide” up and down.

A fixture 2418, which acts at least in part as a sleeve bearing for theshaft 2416, provides positional and rotational stability to both theshaft 2416 and the turbine 2419 attached thereto. A conical extension2420 of the bottom portion of the turbine 2419 reduces drag with respectto the fluid flowing through, within, and/or relative to, the tube 2413.The fixture 2418 is structurally, and positionally, stabilized by atleast two struts, e.g. 2417.

The pod-turbine assembly (2414-2420) positions, and maintains theposition of, the turbine 2419 within the throat 2408 of the tube 2413without the benefit of fixtures, structures, couplers, and/or otherattachments to and/or within the tube. While only two radial pod fins,e.g. 2415, are illustrated, the use of three or more might be expectedto provide more robust positional and rotational stability for the shaftand turbine, and all such embodiment variations are included within thescope of the present disclosure.

FIG. 18B illustrates the lifting of the pod-turbine assembly (2414-2420)upward 2421 and away from its operational position. Note that theassembly moves vertically within the radially-restrictive slots in whichthe radial pod fins are engaged.

FIG. 18C illustrates the complete removal 2421 and separation of thepod-turbine assembly (2414-2420) from the device 2400 by means of theassembly's passage through a hole in the buoy 2400. Note that theradially-restrictive slots in which the radial pod fins are engagedextend through the buoy's hole near, and/or up to, the buoy's uppersurface 2400.

Note that the constricted tube 2406-2411 is now “empty” except for thewater therein.

FIGS. 18D and 18E illustrate the insertion and lowering 2424 of a “tubescrubbing” apparatus 2422-2423, and 2425, into the sameradially-restrictive slots in which the radial pod fins were engaged.These same radially-restrictive slots now engage and fix the lateral andradial position of “cleaner fins”, e.g. 2423, which hold, and providerotational stability to, the shaft of the tube scrubbing apparatus.

FIG. 18F illustrates the tube scrubbing apparatus 2423, 2425-2428 in itsoperational position just above the upper mouth 2405 of the constrictedtube 2413. Note that the “scrubber” 2426-2428 is in a fully collapsedconfiguration in which its diameter is minimal. Also note that an upperportion of the shaft 2422 to which the scrubber is connected and/orattached, extends through the hole in buoy 2400, and is thereforeaccessible above the buoy 2400 and above the surface 2401 of the body ofwater adjacent to which the device floats.

FIGS. 18G-18I illustrate the lateral and/or radial extension of thescrubber 2427 and/or of the scrubbing pads, e.g. 2427, attached thereto,so as to place the outer surfaces of the scrubbing pads in proximity to,and/or in contact with, the inner walls of the tube 2413.

FIGS. 18G-18I also illustrate the rotation 2433 of the shaft 2422 towhich the scrubber 2427 is attached, about the shaft's longitudinaland/or rotational axis 2432. The rotation of the scrubbing pads, e.g.2427, while those pads are in proximity to, if not contact with, theinner walls of the tube 2413 permit the mechanical removal of some, ifnot all, “bio-fouling” marine organisms, corrosion products, films,and/or other accumulated and unwanted materials that reduce theeffective diameter of each part of the tube, and/or which promote theaccelerated and/or further degradation, corrosion, damage, and/ordestruction, of the tube wall.

Because the pod-turbine assembly has been completely removed, and noother impediments to access remain, the tube scrubber is able to scruband/or clean the entire inner surface of the tube. The ability to“clean” the inner and/or operational surfaces of the constricted tube2413 is a useful option and/or feature.

FIGS. 19-24 are cross-sectional-perspective illustrations of anembodiment of the invention disclosed herein. This series of figuresillustrate some, but not all, of the various pod features, designs,configurations, placements, linkages, etc., that are disclosed herein.These illustrations are provided as examples, and in no way limit thesubstantial variety of pod features, designs, configurations,placements, linkages, etc., that are included within the scope of thisdisclosure, said variations being obvious to those skilled in the art ascommon-sense adaptations of the present disclosure to the variety ofspecific cases, objectives, environments, and/or other real-worldconstraints that one might expect to encounter in the present and in thefuture.

FIG. 19 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein. In this embodiment, a pill-shaped pod1108 shares a longitudinal axis with that of the heave point-absorber1100 of which it is a part. The pod 1108 is located above the uppermouth 1119 of the tube 1113-1117. A bi-directional turbine 1118 rotateswithin two conical fixtures, e.g. 1130, and transmits, via a shaft 1111,rotational kinetic energy to the inside of the pod 1108, e.g. where itmight be connected to a generator, an alternator, a water pump, etc.

FIG. 20 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein. In this embodiment, a pod 1208, withconical upper and lower caps, shares a longitudinal axis with that ofthe heave point-absorber 1200 of which it is a part. The pod 1208 islocated entirely within the tube, i.e. inside the tube and between itstwo mouths 1219 and 1220.

FIG. 21 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein. In this embodiment, a pod 1308, withconical upper and lower caps, shares a longitudinal axis with that ofthe heave point-absorber 1300 of which it is a part. The lower portionof the pod 1308 is located within the tube, i.e. inside the tube andbetween its two mouths 1319 and 1320, while the upper portion of the pod1308 is located outside and above the tube. This length of this pod 1308is relatively greater than the lengths of the pods illustrated in FIGS.19-20 . Such longer pods might provide space for additional generatorsand/or it might provide a greater pod volume, and therefore accommodatea greater volume of gas or oil, thereby reducing the likelihood thatwater, perhaps momentarily, penetrating the pod, e.g. through theaperture through which a shaft enters the pod, will reach and perhapsdamage any components therein.

FIG. 22 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein. In this embodiment, a pod 1408, withconical upper and lower caps, does not share a longitudinal axis withthat of the heave point-absorber 1400 of which it is a part. The pod1408 is completely outside the tube, and even outside an upward and/ordownward projection of the tube (e.g. through vertical extensions of therespective tube mouths).

Turbine 1418 transmits rotational kinetic energy to a shaft 1411. Thatshaft 1411, in turn, transmits rotational kinetic energy to a secondshaft 1438, possessing a rotational axis approximately normal to therotational axis of the first shaft 1411, via a coupler 1437 (e.g.perhaps utilizing bevel gears). That second shaft 1438 transmitsrotational kinetic energy to a third shaft 1440, possessing a rotationalaxis approximately normal to the rotational axis of the second shaft1437, and approximately parallel to the rotational axis of the firstshaft 1411, via a coupler 1439 (e.g. again perhaps utilizing bevelgears). The third shaft 1440 then enters the pod where its rotationalenergy may be transmitted to a generator, an alternator, a water pump,etc.

FIG. 23 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein. In this embodiment, a pod 1508, withconical upper and lower caps, does not share a longitudinal axis withthat of the heave point-absorber 1500 of which it is a part. The pod1508 is completely outside the tube, and even outside an upward and/ordownward projection of the tube (e.g. through vertical extensions of therespective tube mouths).

Turbine 1518 is a horizontal-axis turbine that transmits rotationalkinetic energy to a first shaft 1538 that turns about a rotational axisthat is not parallel to the longitudinal axis of the tube 1513-1517.That first shaft 1538 transmits rotational kinetic energy to a secondshaft 1540, possessing a rotational axis approximately normal to therotational axis of the first shaft 1538, and approximately parallel tothe longitudinal axis of the tube 1513-1517, via a coupler 1539 (e.g.perhaps utilizing bevel gears). The second shaft 1540 then enters thepod where its rotational energy may be transmitted to a generator, analternator, a water pump, etc.

FIG. 24 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein. In this embodiment, a pod 1608 sharesa longitudinal axis with that of the heave point-absorber 1600 of whichit is a part. The bottom of the pod 1608 extends down to the turbine1618 to which it is connected. One embodiment has a shaft connecting theturbine 1618 to at least one generator within the pod by means of ashaft that is positioned entirely within the pod 1608.

FIG. 25 is an illustration of one of the many types of turbines that arecompatible with, and included within, the scope of the currentdisclosure. The turbine examples provided in this disclosure in no waylimit the extent of the scope of this disclosure. The substitution ofmany other, if not all other, types of turbines into embodiments of thepresent disclosure would be obvious to those skilled in the art.

The turbine 2502 illustrated in FIG. 25 is composed of rigid blades thatdo not change their orientation with respect to the shaft 2500 to whichthey are directly and/or indirectly connected and/or attached, e.g. theyare “fixed” and though they rotate 2501 about the shaft 2500 to whichthey are attached, they do not rotate about their own blade-specificshafts and/or axes nor in any other way more, nor change theirorientation relative to their neighboring blades and/or the shaft aboutwhich they rotate.

FIG. 26 is an illustration of one of the many types of turbines that arecompatible with, and included within, the scope of the currentdisclosure. The turbine examples provided in this disclosure in no waylimit the extent of the scope of this disclosure. The substitution ofmany other, if not all other, types of turbines into embodiments of thepresent disclosure would be obvious to those skilled in the art.

The turbine 2602 illustrated in FIG. 26 is a bi-directional turbine, andis composed of blades that are able to rotate about their ownblade-specific shafts, and/or otherwise change their orientation, flex,move, etc., so as to change their orientation relative to theirneighboring blades and/or relative to the shaft 2600 about which theyrotate 2607. The blades, e.g. 2604, illustrated in FIG. 26 are able torotate through the plane of the turbine's rotation so as to adopt one oftwo different angular orientations, e.g. 2603 and 2605. When water flowsthrough the turbine 2602 in a downward direction, the blades move to acorresponding downward orientation until they reach a limiting maximallydeflected orientation, e.g. 2605. This causes the turbine 2602 andattached shaft 2600 to rotate 2607.

When water flows through the turbine 2602 in an upward direction, theblades move to a corresponding upward orientation until they reach alimiting maximally deflected orientation, e.g. 2603. This causes theturbine 2602 and attached shaft 2600 to rotate 2607 in the samedirection as when the water flowed in the opposite direction.

FIG. 27 is an illustration of one of the many types of turbines that arecompatible with, and included within, the scope of the currentdisclosure. The turbine examples provided in this disclosure in no waylimit the extent of the scope of this disclosure. The substitution ofmany other, if not all other, types of turbines into embodiments of thepresent disclosure would be obvious to those skilled in the art.

The turbine 2701 illustrated in FIG. 27 is similar to the oneillustrated in FIG. 26 , except that the embodiment illustrated in FIG.27 has two rows of moveable and/or rotatable blades, e.g. 2702 and 2704.

FIG. 28 is a cross-sectional-perspective illustration of an embodimentof the invention disclosed herein. In this embodiment, a pod 2807 isfilled with a gas so as to exclude the water in which the device 2800floats. Due to absorption of its gases into the water over time, and/ordue to the forceful intrusion of water, e.g. through the aperturethrough which the shaft penetrates the pod's wall, it is beneficial toreplenish, augment, and/or augment, that gas with additional gas.

The embodiment illustrated in FIG. 28 replenishes the gas in the pod2807 by utilizing a pump 2805 which draws air 2802 in from theatmosphere through a tube 2803, pressurizes it, and transmits suchpressurized air through a tube 2804 and 2809 into, and through, the baseof the pod 2807.

In one embodiment, the pump transmits additional pressurized air to thepod 2807 in response to a signal generated by a sensor positioned withinthe pod, e.g. a sensor which indicates that the volume of air in the pod2807 has been reduced to and/or below a threshold volume. Many suchsensors would be suitable to this function, including those which use afloat to measure the level of water at the bottom of the pod, thosewhich use and analyze audio signals to determine the resonance, and/orchanges in the resonance, of the air-filled chamber, etc.

In one embodiment, the pump transmits additional pressurized air to thepod 2807 periodically.

In one embodiment, the pump transmits additional pressurized air to thepod 2807 continuously, which one might expect to cause bubbles ofsurplus air to escape the pod and rise to the surface.

In one embodiment, the pumping module 2805 dehumidifies the air that ittransmits to the pod 2807.

In one embodiment, the pumping module 2805 filters out at least asubstantial portion of the oxygen in the air prior to transmitting theresulting gas, primarily composed of nitrogen, to the pod 2807.

FIG. 29 illustrates the use of a pressurized canister 2910 of gaslocated within the pod 2907 that releases (additional) gas into the podas needed. The contents of the canister 2910 may be recharged from thesurface through a port 2905. This pressurized canister's provision ofgas into the pod chamber is supplemented by a mechanical pump 2902located in the buoy.

FIG. 30 illustrates the use of a canister 3005 of compressed gas,regulated and/or controlled by a valve 3002, to maintain, recharge,and/or replace, the gas within the chamber of the pod 3007.

FIG. 31 illustrates the use of a pump 3109 located within the pod 3105that is driven by the rotational kinetic energy transmitted into the podby the shaft 3111. As the pump 3109 is driven by the turning of theshaft 3111 it draws air from the atmosphere through a port 3102 anddischarges it (under pressure) into the chamber of the pod 3105.

FIG. 32 illustrates the use of a complementary pair of pumps 3205 and3209 which cooperatively draw air from the atmosphere through port 3202and discharge it into the chamber of the pod 3207. Pump 3205 is drivenby wave surge 3206, while pump 3209 is driven by the verticaloscillations 3212 of the device 3200 that occur in response to the heaveof the waves passing beneath it.

FIG. 33 illustrates the use of a “suction-driven” pump 3311. As water isaccelerated through the constriction 3312, 3316-3317 in the tube 3322,the water's lateral pressure is diminished. This reduction in lateralwater pressure is transmitted, via ports 3314 and 3319, and tubes 3313and 3315, respectively, to the pump 3311 where it is used to draw airfrom the atmosphere through port 3302 and discharge it into the chamberof the pod 3305.

FIG. 34 is an illustration of a pod consistent with embodiments of thisdisclosure. This pod 3402 uses the rotational kinetic energy transmittedto it from the turbine by means of shaft 3413 to turn the shafts of amultitude of water pumps, 3403 and 3410-3412. These pumps draw waterfrom the body of water surrounding it, through ports 3406-3409, andinject it into a shared conduit 3401 which returns pressurized water tothe buoy, where, for instance, a water driven turbine, such as a “Peltonturbine”, may be used to convert the stream of pressured water back intorotational kinetic energy which might then be used to turn a generatorwithin the buoy.

FIG. 35A is an illustration of a pod consistent with embodiments of thisdisclosure. This pod 3500 uses the rotational kinetic energy transmittedto it from the turbine by means of shaft 3506 to drive a multitude ofgenerators 3507-3514. This pod utilizes a “baffle” 3521 above the pod'saperture 3524 in order to reduce the likelihood of water splashing onthe generators. It supplements the baffle with a circular plate 3518attached to, and/or incorporated within, the shaft 3506 to accomplishthis barrier to water penetration. FIG. 35B is a cross-sectional view ofthe pod showing the generators, e.g. 3532, and the pod wall 3525.

FIG. 36 is an illustration of a pod consistent with embodiments of thisdisclosure. This figure illustrates the use of a single generator 3507.A cable 3602 carries generated electrical power out of the pod, e.g. upto the buoy. Cable 3602 might also carry controlling signals down to analternator 3507, thereby adjusting its response to variations in thetorque and/or speed of the attached turbine and/or shaft 3601. A tube3605 delivers pressurized gas, e.g. nitrogen, and/or oil, and/or someother fluid different in chemical composition from the body of water inwhich the respective embodiment floats. Note that the “unoccupiedvolume”, i.e. the volume available to be filled with gas and/or somealternate fluid, of the chamber is approximately 10 times the volume ofthe generator.

FIG. 37 is an illustration of a pod 3700 consistent with embodiments ofthis disclosure. This figure illustrates the use of multiple baffles,e.g. 3703, a “surge plate” 3708 attached to the shaft 3702. It alsoillustrates the use of a “stuffing box” or other seal to limit theingress of ambient water into the chamber of the pod 3700.

FIG. 38 is an illustration of a pod 3800 consistent with embodiments ofthis disclosure. Note that the “unoccupied volume”, i.e. the volume 3803available to be filled with gas and/or some alternate fluid, of thechamber is approximately 40 percent the volume of the generator 3801.

FIG. 39 is an illustration of a pod 3900 consistent with embodiments ofthis disclosure. This pod incorporates a mechanism that facilitates acontinuous dehumidification of the gas within the pod's chamber. Fans,e.g. 3902, and/or blades, attached to the shaft 3909 turn as the shaftto which they are attached turns. The turning of the fans drives gasdown through a passage established by a tube 3903 and 3905, and/or bywalls 3093 and 3905. Near the bottom portion of the pod's chamber thecirculating gas encounters the chilled surfaces 3906C and 3907C of apair of Peltier coolers. The corresponding “hot” surfaces 3906H and3907H of these Peltier coolers are exposed to the body of the water inwhich the corresponding embodiment floats.

The chilled surfaces 3906C and 3907C condense some or all of themoisture present in the circulating water and some of that water, e.g.3908, falls to the base of the pod where it accumulates 3910. Asubsequent addition of gas to the pod, e.g. through tube 3911, will pushwater accumulated at the bottom of the pod out through the shaftaperture 3912. In this way, humidity is removed and/or minimized withinthe pod thus minimizing any associated corrosion of, and/or damage to,the various components within the pod.

FIG. 40 illustrates an embodiment 4000 of the present disclosure. Thisembodiment periodically adds an anti-biofouling agent, e.g. a coppersolution, to the water inside its constricted tube 4015. The agent maybe added 4003 to a tank 4006 within the buoy 4000 via a port 4002. Itmay also be generated, e.g. from constituent components, e.g. from solidcopper combined with water from the body of water 4001 on which theembodiment floats, by a module 4008 where it is added 4007 to the tank4006. This agent then travels 4014 down a tube 4009 where it exitsthrough one or more ports, e.g. 4022, adjacent to the tube's throat4023.

FIG. 41 illustrates an optional feature of the present disclosure. Agenerator 4101 within a pod 4100 is rotatably connected to a turbine4119 by a shaft 4114. A portion of this shaft incorporates a buoyantmaterial 4113, and/or a tube of a buoyant material 4113 is attached tothe shaft 4114. The coupling of the buoyant material 4113 to the shaft4114 reduces and/or offsets the mass and/or weight of the shaft andattached turbine. This addition of a buoyant material to a shaft cansignificantly reduce the load on any bearings, e.g. thrust bearings 4105and 4107, thus reducing the cost and/or extending the operationallifetime of the embodiment so modified.

FIG. 42 illustrates an unusual, but potential, embodiment of the presentdisclosure. This embodiment 4200 uses a turbine 4207, and its attachedshaft 4209, to turn 4214 a pod housing 4212, within which is a generator4216 that is rigidly attached to this rotatable pod housing. Thegenerator's 4216 shaft 4218 is fixed to the embodiment's frame 4219 and4220, which thereby precludes any turning of the generator's shaft 4218.Thus, in this embodiment, the generator turns and its shaft does not.

FIG. 43 illustrates an embodiment of the present disclosure in which thesubmerged constricted tube 4310 is suspended by a flexible connector4302 attached a point 4309 offset from the longitudinal axis 4304 of thetube. Because of this, the tube tends to adopt an orientation which isnot entirely vertical. Vertical oscillations 4303 of the embodimentresulting from the passage of waves will tend to introduce water intothe tube 4310 from a non-axial direction.

FIG. 44 illustrates an embodiment of the present disclosure in which aspherical and/or ellipsoidally-shaped buoy 4400 holds, via a flexibleconnector 4404, a constricted tube 4410. Multiple connectors, e.g. 4402,link the single common connector 4404 to the buoy 4400. Multipleconnectors, e.g. 4406, also link the single common connector 4404 to thetube 4410. a cage 4407 protects and/or shields the pod 4408 fromcollisions with the connectors, e.g. 4406.

FIG. 45 illustrates an embodiment of the present disclosure in which aconstricted tube 4513 is suspended by at least a pair of flexibleconnectors, e.g. 4503, from an approximately cylindrical buoy 4500. Theflexible connectors are separated and/or spaced about the tube 4513 by apair of extensions, e.g. 4510, and are attached to the tube 4513 atpoints, e.g. 4512, below the top of the tube.

FIGS. 46A and 46B illustrate an embodiment 4600 of the presentdisclosure in which an interior constricted channel 4613 and 4608, isseparated from the body of water 4601 in which the embodiment floats byan outer wall or hull 4607. Between the inner and outer walls is a void4606. In one embodiment, the void 4606 is filled with material having adensity greater than that of the water in which the embodiment floats soas to promote the tube's sinking.

FIGS. 47A and 47B illustrate an embodiment 4700 of the presentdisclosure in which the buoy portion 4700 has a hole 4702 allowing theatmosphere to communicate with the body of water 4710 on which theembodiment floats. Like the embodiment illustrated in FIG. 46 , thesubmerged tube 4723 of this embodiment 4700 contains an interior 4717and exterior 4721 wall, thereby creating a void 4713 between. The shapeof the outer wall is convex 4719 and the position of its maximumdiameter 4718 does not coincide with the vertical center 4720 of thetube.

FIG. 48 illustrates an embodiment 4800 of the present disclosure inwhich the submerged tube 4808 is attached and/or connected to the buoy4800 by flexible connectors, e.g. 4805, that connect to the buoy bymeans of rigid extensions, e.g. 4802, from the buoy.

Like the embodiments illustrated in FIGS. 46 and 47 , the submerged tube4808 of this embodiment 4800 contains an interior 4813 and exterior 4811wall, thereby creating a void 4810 between. The shape of the outer wallis convex and the position of its maximum diameter does not coincidewith the vertical center of the tube. Moreover, in this embodiment, thevoid 4810 is filled with a material whose density is greater than thatof water, thereby promoting the sinking 4815 of the tube.

FIG. 49 illustrates an embodiment 4900 of the present disclosure inwhich the submerged tube 4908 is attached and/or connected to the buoy4900 by flexible connectors, e.g. 4905, that connect to the buoy bymeans of v-shaped flexible connectors, e.g. 4902-4903, connected to thebuoy.

Like the embodiments illustrated in FIGS. 46-48 , the submerged tube4908 of this embodiment 4900 contains an interior 4907 and exterior 4916wall, thereby creating a void 4917 between. The shape of the outer wallis cylindrical.

In this embodiment a horizontal-axis turbine 4919 communicatesrotational kinetic energy to a pulley or gear 4914, which turns and/orrotates a belt or chain 4913. A complementary pulley or gear 4912receives the rotational kinetic energy and its attached shaftcommunicates it to a bevel-gear assembly 4911 that communicates therotational kinetic energy to shaft 4910, and thereby communicates to theinside of the pod 4909 mounted on the side of the tube 4918 by theextension 4906.

FIGS. 50A and 50B illustrate an embodiment 5000 of the presentdisclosure in which the submerged tube 5017 is attached and/or connectedto the buoy 5000 by flexible connectors, e.g. 5002.

Like the embodiments illustrated in FIGS. 46-49 , the submerged tube5017 of this embodiment 5000 contains an interior 5012 and exterior 5011wall, thereby creating a void between. The shape of the outer wall iscylindrical and its diameter is greater than the greatest diameter ofthe interior channel.

In this embodiment a vertical-axis turbine 5013 communicates rotationalkinetic energy to a pulley or gear 5010, which turns and/or rotates agear 5009 that extends, through an opening 5015 in the interior wall,into the channel. Because of its relatively narrow “spokes”, e.g. 5020,water is able to flow 5014 through the channel without significantdisruption. At another point along the gear 5009, a gear 5007 extractsfrom the gear 5009 rotational kinetic energy which it communicates to ashaft 5006 which extends to the inside of a pod 5005.

FIG. 51 illustrates an embodiment 5100 of the present disclosure inwhich an exterior half 5103 of a “magnetic coupler” or “magneticcoupling” communicates rotational kinetic energy from the shaft 5104 andits attached turbine 5105 to the other complementary half of themagnetic coupler positioned inside the pod 5102. This embodiment enjoysthe benefit of a hermetically sealed pod which is completely isolatedfrom the water that surrounds it.

FIG. 52A better illustrates the hermetically sealed pod 5200 illustratedin FIG. 51 . One half 5206 and/or component of a magnetic coupler isattached to a shaft 5207 which, in turn, is attached to an embodiment'sturbine. As the shaft 5207 and magnetic coupler 5206 turn, under theinfluence of the attached turbine, the magnets, e.g. 5205, on its uppersurface, engage with magnets, e.g. 5204, on the lower surface of thecomplementary half 5203 of the magnetic coupler. The half 5203 of themagnet coupler inside the pod 5200 is attached to a shaft 5202 which isattached to generator 5201. Note that the pod's wall 5200 contains noopenings or apertures through which gas can escape and/or through whichwater can enter. Configurations of magnetic couplers may include matedplate (“axial frontal”) configurations as shown, as well as radialconcentric configurations and others.

At the right side of FIG. 52B is a top down view 5208 of the magneticcoupler 5206. It is attached to shaft 5207 at 5210. And, it incorporatesa circular array of magnets, e.g. 5209, on its upper surface.

FIG. 53 is an illustration of a pod 5300 with two chambers. An upperchamber 5303 is hermetically sealed. An adjoining lower chamber 5311 isopen to a surrounding body of water. The rotation of shaft 5314 causesthe rotation of one half of a magnetic coupling, composed of a bottomplate 5310 and a concentric ring of magnets, e.g. 5309 and 5313 (similarto the plate 5208 and ring of magnets, e.g. 5209, illustrated in FIG.52B.

As the lower half 5310 of the magnetic coupling is rotated 5315, theinterlinked magnetic fields between the lower 5310 and upper 5305 halvesof the magnet coupler cause a correlated rotation 5306 of the upper half5305 of the coupler. The induced rotation 5306 of the upper half 5305 ofthe magnet coupler, and the attached shaft 5304, causes the rotation ofthe rotor of the generator 5301, thereby generating electrical powerthat is transmitted to the buoy at the surface via power cable 5302.

Gas, and/or another appropriate fluid, is transmitted 5316 into thelower chamber 5311 via a tube 5317, thereby refreshing, replenishingand/or replacing the gas and/or other fluid nominally trapped in thatchamber.

FIG. 54 illustrates an embodiment of the present disclosure in which aconstricted tube 5417 is suspended beneath a flotation module 5401 bychains 5413 and 5416. As the embodiment moves up and down in response towaves moving across the surface 5400 of the body of water in which theembodiment floats, water moves down and up, respectively, through theconstricted tube 5417. The speed of the water flowing through the tubeis multiplied by the constriction, and, at or near its point of greatestlongitudinal speed (e.g. inside the tube's throat), a bi-directionalturbine 5420 extracts energy from the flow and is thereby rotated.

The rotation of the turbine 5420 causes the rotation of the attachedshaft 5415, which, in turn, rotates the rotor of a generator 5412 ofchemical fuel(s). The generated and/or synthesized chemical fuels aretransmitted to the flotation module 5401 through a tube 5411.

One embodiment generates the chemical fuel(s), at least in part, fromwater that it draws in 5414 from the ambient body of water 5400. Anotherembodiment generates the chemical fuel(s), at least in part, fromprecursor chemicals and/or ingredients that it receives from a tank 5409positioned within the flotation module 5401. The flow of precursorchemicals to the generator 5412 is regulated, pumped, and/or controlled,by a module 5406. And, the flow of precursor chemicals reaches thegenerator 5412 via a tube 5407. Yet another embodiment generates thechemical fuel(s), at least in part, from both ambient water andprecursor chemicals.

One embodiment stores at least a portion of the synthesized chemicalfuel(s) in a holding tank 5410 which may be emptied via access port5403. Another embodiment transmits at least a portion of the synthesizedchemical fuel(s) to an external storage container, pipeline, tube,and/or “consumer” (e.g. device that uses the chemical fuel(s) togenerate energy), via port 5404, e.g. via a tube like 5405.

Note that tube 5417 has a “double wall”, e.g. 5417 and 5418, and aninternal void 5419.

FIG. 55 illustrates an embodiment of the present disclosure in which thepod is defined, and/or instantiated, at least in part, by at least oneof the components being positioned, operated, and/or “protected” (e.g.from the surrounding water). In other words, one portion of the pod'swall, or physical barrier, which excludes the surrounding water, and/ortraps the “protective fluid or gas”, is composed, at least in part, ofat least a portion of at least one of the components enjoying theprotection of at least one of the pod's protected chambers.

At least a portion of the outer casing 5506 and/or shell of thegenerator 5507 effectively creates at least a portion of the upper wallof the pod 5512. The junction between the exterior generator casing 5506and the pod wall 5508 is sufficiently tight and/or sealed so as toprevent significant leakage of ambient outside water into the pod's 5512inner chamber. At least a portion 5509 of the outer casing of anothercomponent, e.g. a rectifier, effectively creates at least a portion ofthe side wall of the pod 5512.

This embodiment illustrates the ability of a water-tight “pod” chamber,containing a fluid (e.g. or gas) that chemically differs from the water5500 outside the pod, to be established, composed, created, defined,and/or instantiated, by composite barriers including at least in partcontributions from the outer surfaces of the components positioned,operated, and/or protected, inside the pod.

By extending one side 5506 of the generator 5507 into the water, andplacing that portion of the generator's exterior into contact with thewater, the water may serve as a heat sink for the generator and help toprevent the generator from overheating. Likewise, by extending one side5509 of the rectifier into the water, and placing that portion of therectifier's exterior into contact with the water, the water may serve asa heat sink for the rectifier and help to prevent the rectifier fromoverheating.

Note that the pod 5512 is held in position above the upper mouth of theconstricted tube 5517 by struts, e.g. 5513.

Note that the pod 5512, tube 5517 and turbine 5516 assembly, which isrigidly interconnected, is connected to the flotation module 5501 byconnectors 5504 and 5505 that are attached to the bottom of theflotation module 5501 at a single point 5502. This single point 5502 ofconnection allows the pod, tube, turbine assembly to “rock” 5503 and/orswing about the point 5502 of connection thereby at least partiallydecoupling the motions of the assembly and the flotation module. In oneembodiment, the connectors 5504 and 5505 are flexible (e.g. cables,chains, ropes, etc.). In another embodiment, the connectors 5504 and5505 are rigid.

Note that two additional flexible connectors 5510 and 5511 arerelatively “loose” (i.e. not “tight”) and allow the pod, turbine, tubeassembly to swing 5503 to at least a significant degree. However, thesetwo additional flexible connectors 5510 and 5511 prevent the pod,turbine, tube assembly from rotating, to any significant degree, aboutits longitudinal axis with respect to the relative orientation of theflotation module.

The variable direct-current (VDC) electrical power output by therectifier 5509 is transmitted to the buoy by the power cable looselywrapped around flexible connector 5510.

FIG. 56 illustrates an embodiment of the present disclosure in which thepod 5613 has two adjacent and/or interconnected chambers. An upper-mostlower wall 5614 protects a generator 5612 by trapping a pocket of a gas(or other fluid) that chemically differs from the surrounding body ofwater 5600. And, a lower-most lower wall 5616 extends the capacity ofthe upper chamber, and further isolates any intrusions of ambient waterand/or splashing from the equipment and/or surfaces positioned withinthe upper-most chamber. Pod 5613 has two lower walls 5614 and 5616, andtwo apertures therein (one per wall) through which the shaft 5619 passesin order to connect the generator 5612 inside the pod to the turbine5621 inside the constricted tube 5620.

One embodiment has two redundant electrical cables 5608 providing powerand/or signals, produced by a power-control module 5605, and used tocontrol an alternator 5612 positioned within, and rigidly affixed to theinside of, a pod 5613. The electrical power produced by the alternator5612 is transmitted to a power-control and/or processing module 5605 bya pair of redundant power transmission cables 5604.

In another embodiment, the electrical power produced by a generator 5612is transmitted to a power-control and/or processing module 5605 by fourredundant power transmission cables 5604 and 5608.

In one embodiment the generation of power is controlled, adjusted,and/or regulated, at least in part, by signals transmitted to the device5601 via signal transmission wires and/or cables 5603 and 5606.

In one embodiment, power generated by at least one other device istransmitted to the device 5601 via power cable 5603, and the powergenerated by the device 5601, as well as the power transmitted to it, istransmitted away from the device by a power cable 5606.

FIG. 57 illustrates an embodiment of the present disclosure in which theconstricted tube is not radially symmetrical about a single longitudinalaxis. As this embodiment is driven up and down by waves passing acrossthe surface 5700 of a body of water, water enters and/or exits the tube5708 “off-axis”, i.e. in a direction not parallel to a longitudinal axisof the tube. Under certain circumstances such a design might be expectedto increase device power.

Note that the pod 5705, shaft 5709, and turbine 5714 of this embodimentare not coaxial with a longitudinal axis of the constricted tube 5708.Note that the portions 5711 and 5716 of the tube lacking a constantcross-sectional area are asymmetrical, i.e. the widest and narrowestportions of each portion are not coaxial with respect to a locallongitudinal axis. Note that the planes in which the “mouths” of thethroat are defined are not parallel, and that the turbine's plane ofrotation is not parallel to the planes of either mouth.

Note that the constricted tube 5708 in this embodiment is suspendedbeneath two independent flotation modules 5701 and 5702 by flexibleconnectors (e.g. chains, cables, ropes, etc.) 5706 and 5707.

FIG. 58 illustrates an embodiment of the present disclosure in which asingle flotation module (buoy) 5801 supports a conjoined pair 5812 and5817 of constricted tubes, which share common “cuff” portions, e.g.5819, characterized by approximately constant cross-sectional areas. Theconstricted tube(s) are connected to the buoy 5801 by flexibleconnectors 5803 and 5805 which allow the longitudinal axis 5804 of thetube(s) to move away from its nominal coaxial orientation with respectto the longitudinal (and/or vertical) axis of the buoy 5801.

This embodiment possesses two pods 5806 and 5807, two shafts 5808 and5809, and two contra-rotating turbines 5820 and 5821 driven by waterflowing through two throats 5812 and 5817.

FIG. 59 illustrates an embodiment of the present disclosure in which asingle flotation module 5901 supports two independent constricted tubes5905 and 5911. Because the two tubes are connected to the flotationmodule 5901 and to each other by flexible connectors 5902 and 5903, allthree are able to have longitudinal axes that are not coaxial at somemoments, and that are coaxial at others.

Note that in this embodiment the two turbines 5909 and 5915 are belowthe lower mouths 5916 and 5917 of their respective tubes 5905 and 5911,i.e. these turbines are “outside” of their respective constricted tubes,and are driven by water accelerated by the constricted tubes, but onlyafter the respective accelerated streams of water have travelled out ofthe tubes and back into the body 5900 of water from which theyoriginated.

FIG. 60 illustrates an embodiment of the present disclosure in which asingle pod 6004, possessing a single aperture 6012, through which passesa single shaft 6011, rotationally energizes two separate generators 6009and 6010 that are positioned in two separate “sub-chambers” (left andright) within the pod 6004. The pod's interior is bifurcated into twoseparate branches, each containing a single generator 6009 and 6010. Inthis embodiment, the generators 6009 and 6010 are positioned and/orattached to lower-most pod walls.

This embodiment contains a constricted tube 6013 possessing two separatethroats 6017 and 6023 in which two turbines 6018 and 6024, connected bya shared single shaft 6011, are driven by a flow that is acceleratedtwice, i.e. once in each constricted tube portion or segment.

FIG. 61 illustrates an embodiment of the present disclosure in which asingle pod 6107 possesses two different apertures 6112 and 6114, each ofwhich provides access to a shaft 6111 and 6115, respectively. In thisembodiment, two generators 6106 and 6108 are located in the center ofthe pod and are driven by shafts 6105 and 6109 that project from them inoutward, opposite directions.

In this embodiment, the power extracted by turbines 6119 and 6120, beingdriven by two constricted tubes 6116 and 6117, possessing parallellongitudinal axes, are transmitted by two shafts 6111 and 6115, into asingle, common, shared pod 6107 that converts the power extracted fromboth turbines and tubes into electrical power.

The two constricted tubes 6116 and 6117 are rigidly joined by structure6113, 6118 and 6121, which also rigidly positions the shared pod 6107.And, the entire tube and pod assembly is rigidly attached to theflotation module 6101 by rigid struts 6102 and 6103.

FIG. 62 illustrates an embodiment of the present disclosure in which twoturbines 6222 and 6224, that are connected to, and spin in synchronywith, a common, shared shaft 6216, are located above and below,respectively, (i.e. outside) the throat 6219 (or plane of minimumcross-sectional area) of the constricted tube 6217-6221.

In this embodiment, the turbines 6222 and 6224 do not obstruct the flowof water through the tube at its point of minimum cross-sectional area,and yet the throat, which possesses a smaller cross-sectional area thaneither of the turbines, may “choke the flow” (i.e. obstruct through aloss of lateral pressure, through a vaporization of water when the waterpressure falls below the “vapor pressure” of the flowing water, and/orthrough the generation of turbulence and/or through the disruption of alaminar flow) in response to extreme wave conditions and thereby provideat least a measure of vertical positional stability to the device duringsuch extreme wave conditions.

In this embodiment, a single turbine shaft 6216 interfaces 6211 with anddrives two other shafts 6207 and 6208, each of which drives a respectivegenerator 6205 and 6206 positioned in its own respective pod 6225 and6226. In this embodiment, shafts enter their respective pods 6225 and6226 through apertures located in the side walls of the respective pods.

The three-phase electrical power generated by each generator isconverted into variable DC power by a rectifier 6203 and 6204 and theresulting DC power from each pod is transmitted to the buoy 6201floating adjacent to the surface 6200 of a body of water by cables 6202.

FIG. 63 illustrates an embodiment of the present disclosure in which theconstricted tube 6304 is composed of a single frusto-conical element. Aturbine 6317 located outside the tube, and below the lower tube mouth6316, is driven by water 6315 accelerated by the tube 6304 after thewater has exited, and/or passed through, the lower mouth 6316.

This embodiment possesses a bifurcated pod 6322 possessing a single,upward-facing aperture 6318, through which passes and rotates a singleshaft 6319 that drives two generator-specific shafts 6313 and 6314,which in turn drive two generators 6309 and 6310. Because the aperture6318 is upward-facing, it is unable to trap a gas or buoyant-fluid.Therefore, the lower portion 6322 of the pod is “flooded” with waterfrom the surrounding body 6300 of water. Gas and/or buoyant fluid forcedinto the pod through tubes 6307 and 6308 rises to fill each respectivehalf 6311 and 6312 of the inverted portion of the pod.

Note the exemplary sleeve bearings 6323 and 6324 that provide positionaland rotational stability to the respective shafts.

FIG. 64 illustrates an embodiment of the present disclosure in which asingle constricted tube 6413-6417 accelerates a flow of water thatdrives two independent turbines 6424 and 6431. One turbine 6424 is avertical-axis turbine in which the turbine is driven by fluid flowingparallel to its rotational axis. The other turbine 6431 is ahorizontal-axis turbine in which the turbine is driven by fluid flowingnormal to its rotational axis. This embodiment extracts power from anaccelerated flow of water through the use of two turbines 6424 and 6431positioned and operating within a common, single, shared throat 6415.

Each turbine transmits its rotational kinetic energy to a respectiveshaft which drives a respective generator 6407 and 6426. Each respectivegenerator is positioned within an independent respective pod 6406 and6427. This constricted tube 6413-6417 is rigidly connected to two pods6406 and 6427.

The external pod 6406 has an outer casing 6406 and/or wall that excludesthe ambient water 6400 and creates an inner chamber 6428 in which a gasand/or buoyant fluid may be trapped. This pod 6406 is positioned abovethe upper mouth of the tube 6413-6417 by rigid struts, e.g. 6410.

The other pod 6427 has no pod-specific casing and/or walls. Instead, itis fashioned and/or instantiated as an evacuated and/or hollow space6427 embedded within the solid wall 6425 of the constricted tube6413-6417.

The constricted tube has both inner 6419 and outer 6418 walls, and lacksa void between those walls, i.e. is solid 6425.

FIG. 65 illustrates an embodiment of the present disclosure in which theconstricted tube 6515 is a tube of approximately constantcross-sectional area in which an “orifice plate” 6521 creates theconstriction used to amplify the speed of the water flowing 6519 and6520 flowing therethrough.

This embodiment possesses a pod 6507 in which the lower pod wall 6513 isnot contiguous with the lower edge of the pod's side wall 6512. Thiscreates a “secondary” enclosure in which some of the gas and/or buoyantfluid trapped in the pod 6507 that would otherwise escape through thepod's aperture 6513 and pass into the surrounding body 6500 of water canbe trapped and thereby, at least on occasion, reduce the frequency withwhich water is forced into the inner pod chamber 6511, e.g. throughwave-induced surges in the vertical position of the device.

By passing additional gas and/or buoyant fluid from tube 6506 into thepod 6507 below and outside the inner chamber 6511 of the pod, the addedgas and/or buoyant fluid may, as a consequence of its buoyancy, rise upthrough the aperture 6513 and into the inner pod chamber 6511.

In one embodiment, the electrical power generated by the generator 6508is transmitted from the generator in the pod 6507 to the buoy 6501 via apair of redundant power cables 6504 and 6505, each of which transmitspower to redundant power-processing modules 6502 and 6503. In anotherembodiment, an alternator 6508 is controlled by electrical signalsgenerated by an alternator control module 6502, and transmitted to thealternator 6508 via an alternator control cable 6505. The resultingelectrical power generated by the alternator 6508 is transmitted to apower-processing module 6503 (e.g. possessing a rectifier) positioned inthe buoy 6501 via a power-return cable 6504.

FIG. 66 illustrates an embodiment of the present disclosure in which a“self-constricting” turbine, e.g. a “reaction turbine”, a “Francisturbine”, etc., is positioned and/or attached to a tube 6605 with anapproximately constant cross-sectional area. As the device rises andfalls in response to waves passing across the surface 6600 of a body ofwater, water flows down and up, respectively, through the tube 6605. Thetube allows positive pressure to build within the water in the “leading”portion of the tube (the upper portion when the tube is rising and thelower portion when the tube is descending), and negative pressure (i.e.a partial vacuum) in the “trailing” portion of the tube. The resultingpressure differentials drive water, from the higher-pressure portion,e.g. 6610, through the reaction turbine 6611, and into thelower-pressure portion, e.g. 6612, resulting in the production of rotarykinetic energy in the turbine's shaft 6607 which drives a generator in apod 6604.

FIG. 67A illustrates an embodiment of the present disclosure in which apod does not contain a generator. In this embodiment, a serially-linkedand/or connected set of tubes 6711-6715, are moved up and down throughwater at increasing depths d1-d5 by a common, shared flotation module6701 floating adjacent to the surface 6700 of a body of water.

Each pod contains a sensor that measures the “RPM” of each tube'srespective turbine and shaft. Those tubes and turbines moving up anddown through water above the wavebase will be moving within water that,at least to a degree, is moving in synchrony with the waves above andwith the tubes and turbines. Thus, the rotational speeds (i.e. the RPMs)of these turbines and their respective shafts will be lower than theywould be if moving through the relatively still waters at or below thewavebase.

Those tubes and turbines moving up and down through water at or belowthe wavebase will show a maximal and relatively consistent turbine andshaft RPM.

For example, if the embodiment 6701 moves up and down in response towaves associated with a wavebase “wb1” then the turbine and shaft intube 6711 will be expected to have and/or manifest a rotational speedlower than the rotational speeds of the turbines and shafts in tubes6712-6715. And, the rotational speeds of the turbines and shafts intubes 6712-6715 will be expected to have approximately equal, maximal,and/or consistent, values since they are all being driven up and down atapproximately the same rates through water that is approximatelyconsistent in its lack of correlated wave motion.

FIG. 67B illustrates a representative pod characteristic of the podsassociated with tubes 6711-6715 illustrated and discussed in FIG. 67A.Each pod, e.g. 6718, contains an RPM meter or sensor 6720 whichinteracts with, and/or monitors, the rotations, e.g. 6724, of arespective turbine shaft 6721.

One embodiment of the device illustrated in FIG. 67A transmits the shaftrotational rate to the buoy 6701 via an electrical cable 6719.

Another embodiment of the device illustrated in FIG. 67A transmits theshaft rotational rate to the buoy 6701 via audible pulses 6722 generatedand/or produced by a speaker 6723 located within the pod andtransmitting its sound into the surrounding body of water through thepod wall 6718. One or more microphones in the buoy 6701 detect anddifferentiate the sound pulses transmitted into and through the water byeach respective pod within the embodiment.

FIG. 67C graphically illustrates the relation of turbine and shaft RPMto the position of the wavebase. The turbine and shaft RPM of eachdepth-specific tube increases exponentially until the depths of thetubes reach or exceed the wavebase.

The device illustrated in FIG. 67A can be used to detect and/ordetermine the effective wavebase at a particular location in the sea atany moment in time, and to detect and/or determine changes in theeffective wavebase, and/or in the range of effective wavebases,characteristic of a particular location in the sea over a period oftime, e.g. on an annual basis.

This type of information might be used to help optimize the designand/or design parameters of wave energy converters and/or devices priorto their deployment at a particular location in the sea, or other bodyof water.

FIG. 68 illustrates an embodiment of the present disclosure in which aconstricted tube 6811 containing a shaft 6810 and at least one turbineis suspended from a flotation module 6801 such that the suspending forcetransmitted to the tube through a flexible connector 6804 is not coaxialwith the longitudinal axis of the tube, nor with the longitudinal axisand/or axis of buoyancy of the flotation module 6801.

The vertical oscillations of this embodiment's submerged constrictedtube 6811 are not parallel to the longitudinal axis of the tube 6811causing water to enter, e.g. 6807, and exit the tube in directions thatare likewise not parallel to the longitudinal axis of the tube. Thevertical oscillations of the embodiment's submerged constricted tube6811 are not necessarily governed by, nor synchronous with, the verticaloscillations of the waves passing beneath the flotation module 6801, andmay be augmented with and/or corrupted by the “rocking” and/or“swinging” motions, if any, exhibited by the flotation module as itmoves responsive to wave action.

FIG. 69 illustrates an embodiment of the present disclosure in which aset of two or more constricted tubes, e.g. 6907-6909, are suspendedbeneath and/or by respective flotation modules 6901-6903. Each tubepossesses a turbine that spins a rotatably-connected shaft whichenergizes a respective generator in a respective pod 6904-6906. Thepower generated by each tube, turbine, generator, in the set iscombined, fused, and/or joined (e.g. into a composite variable DC powersignal) and passed through one or more power cables 6917 to a consumingdevice 6934 and/or set of consuming devices, and/or to an electricalpower grid 6932 and/or connected set of electrical power grids.

In one embodiment, the collected and/or composite electrical power istransmitted through a power cable that travels to the seafloor and/oradjacent to the interface between the body of water 6900 and the ground6921 beneath.

In one embodiment, the collected and/or composite electrical power istransmitted through a power cable to and/or into at least one electricalprocessing module, e.g. 6925, and/or substation positioned (e.g. byfloating and/or through its attachment to some other structure) and/orlocated adjacent to the surface 6900 of the body of water.

In one embodiment, the collected and/or composite electrical power istransmitted through a power cable to and/or into at least one electricalprocessing module, e.g. 6928, and/or substation positioned and/orlocated adjacent to the interface between the body of water 6900 and theground 6921 beneath.

In one embodiment, the collected and/or composite electrical power istransmitted through a power cable to and/or into at least one electricalprocessing module, e.g. 6930, and/or substation positioned and/orlocated adjacent to the shoreline.

FIG. 70 illustrates an embodiment of the present disclosure in which aconstricted tube 7005 contains and/or incorporates “flaps”, e.g. 7008,which open to permit the flow of water through the underlying apertures,e.g. 7009, and/or holes in the walls of the tube, so as to facilitatethe descent of the tube. The flaps close and effectively create solidtube walls when the device and its submerged constricted tube 7011 riseso as to facilitate its acceleration of the water flowing therethroughand its consequent and related generation of electrical power throughthe turning of the turbine 7014, shaft 7006, and generator (locatedwithin pod 7004).

The configuration illustrated here, i.e. in which the apertures areclosed by their associated flaps would be expected to characterize theascension and/or rising of the embodiment in response to an approachingwave crest.

This embodiment can generate significant amounts of electrical powerwhile utilizing a relatively lightweight tube that, without theflap-covered apertures might be too lightweight to fully descend beforethe start of a new ascension. A lighter-weight tube is potentially lessexpensive and easier to deploy than one of greater weight.

FIG. 71 illustrates the same embodiment illustrated in FIG. 70 .However, in this illustration the flaps are “raised” and the associatedapertures are “open”. Water flows into the inside of the tube 7111through the apertures, e.g. 7109, as well as through the lower mouth7115. The configuration illustrated here, i.e. in which the aperturesare open and not obstructed by their associated flaps would be expectedto characterize the descent and/or falling of the embodiment in responseto an approaching wave trough.

FIG. 72 illustrates an embodiment similar to the embodiment illustratedin FIGS. 70 and 71 . However, in this embodiment the tube is perforatedby a greater number of smaller, and non-rectangular, orifices, which areobstructed, when the device and tube are rising, by flaps that aresimilarly smaller, and non-rectangular, than the flaps illustrated inFIGS. 70 and 71 . In this embodiment, the turbine 7211 is below the tubeand the lower mouth of the tube.

FIG. 73 illustrates an embodiment of the present disclosure in which aconstricted tube 7314 contains and/or incorporates “flaps”, e.g. 7310,which open to permit the flow of water through the underlying apertures,e.g. 7311, and/or holes in the walls of the tube, so as to facilitatethe descent of the tube. Unlike the embodiments illustrated in FIGS.70-72 , this embodiment utilizes a constricted tube in which the broadermouth trails the rising of the tube. And, contrary to embodimentsillustrated in FIGS. 70-72 which tend to generate positive pressurewithin their tubes when those device and their tubes rise, thisembodiment's constricted tube tends to generate negative pressure, i.e.a partial vacuum, within the tube when the device and tube rise.

The turbine 7309 of this embodiment is positioned within (i.e. neitherabove nor below) the upper mouth 7307 of the constricted tube. Theassociated pod 7304 is held in position by rigid struts 7305 and 7306.

The configuration illustrated here, i.e. in which the apertures areclosed by their associated flaps would be expected to characterize theascension and/or rising of the embodiment in response to an approachingwave crest.

FIG. 74 illustrates the same embodiment illustrated in FIG. 73 .However, in this illustration the flaps are “raised” and the associatedapertures are “open”. Water flows into the inside of the tube 7409through the apertures, e.g. 7414, as well as through the lower mouth7416. The configuration illustrated here, i.e. in which the aperturesare open and not obstructed by their associated flaps would be expectedto characterize the descent and/or falling of the embodiment in responseto an approaching wave trough. In the absence of the open apertures,this tube might tend to descend slowly as the broad lower mouth 7416would capture a greater volume of water as the tube falls than the upperrelatively narrow mouth could easily release without a buildup ofpositive pressure, and therefore resistance, within the tube.

This embodiment can generate significant amounts of electrical powerwhile utilizing a relatively lightweight tube that, without theflap-covered apertures might be too lightweight to overcome the drag ofan unperforated tube, and thereby fully descend before the start of anew ascension. A lighter-weight tube is potentially less expensive andeasier to deploy than one of greater weight.

FIG. 75 illustrates an embodiment similar to the embodiments illustratedin FIGS. 70-74 . However, in this embodiment the constricted tube has a“full” and “balanced” constriction possessing a throat 7513 that iscloser to the tube center than to either of the tube mouths 7505 and7520.

This embodiment utilizes flaps, e.g. 7508, that open and close abouthorizontal axes, and/or axes approximately normal to the longitudinalaxis of the tube. It also utilizes flaps, e.g. 7518, that open and closeabout vertical axes, and/or axes approximately parallel to thelongitudinal axis of the tube.

This embodiment utilizes rigid flaps, e.g. 7508, that open and closeabout fixed axes. However, it also utilizes flexible flaps, e.g. 7518,that open and close through deformation of at least a portion of theflap and/or of the material of which the flap is made.

A number of variations of the present disclosure are possible and fallwithin the scope of this disclosure. For instance:

1. Turbines need not be located entirely within, nor even partiallywithin, the throat of an embodiment's constricted tube. Although it ispresumably more efficient to do so.

2. A single constricted tube can be designed to include two or morepoints, zones, and/or portions, of globally or locally maximalconstriction. In other words, a single constricted tube can be designedand fabricated so as to possess two or more throats, in which one mightposition two or more turbines, respectively. These constrictions mightoccur in parallel or in series.

3. One might position two or more distinct turbines, whether or not theyare attached to a common shaft, within a single throat within a singleconstricted tube.

4. The power generated by one or more of these embodiments can and/ormay be transmitted to an electrical “grid” and/or to a consumer ofelectrical power, e.g. onshore, via one or more power cables, whichmight be connected by means of, and/or through, one or more electricalpower “substations.” The scope of the present disclosure includes adevice, as disclosed, or more than one device, as disclosed, connectedto and/or incorporating one or more power cables and one or moreelectrical power substations so as to transmit the generated electricalpower to a location where it may be used. The scope of the presentdisclosure includes embodiments which incorporate such power cables andsubstations.

5. Two or more constricted tubes, of the kind disclosed, each with itsown pod, can be suspended beneath a shared flotation module, buoy, boat,etc.

6. A single constricted tube, with attached and/or connected pod, can beattached to, and/or suspended by, two or more flotation modules, buoys,boats, etc.

We claim:
 1. A positively buoyant wave energy converter, comprising: awater-conducting tube having at least one constriction for acceleratingfluid flowing therein; a fluid channel configured to receive fluidpressurized by water oscillating in the water-conducting tube; a turbinedisposed in the fluid channel; a generator operatively coupled to theturbine for generating electricity from a rotation of the turbine; anenclosure configured to contain a pressurized gas; and a gasreplenishment unit configured to add gas to the enclosure.
 2. Apositively buoyant wave energy converter, comprising: a water-conductingtube having at least one constriction for accelerating fluid flowingtherein; a fluid channel configured to receive fluid pressurized bywater oscillating in the water-conducting tube; a turbine disposed inthe fluid channel; a generator operatively coupled to the turbine forgenerating electricity from a rotation of the turbine; an enclosureconfigured to confine a pressurized gas; and an air pump adapted to addair to the enclosure.
 3. The positively buoyant wave energy converter ofclaim 1, wherein the gas is nitrogen.
 4. The positively buoyant waveenergy converter of claim 1, wherein the gas is air.
 5. The positivelybuoyant wave energy converter of claim 1, wherein the gas is hydrogen.6. The positively buoyant wave energy converter of claim 1, furthercomprising electrolyzing equipment.
 7. The positively buoyant waveenergy converter of claim 1, further comprising a chemical fuelgenerator.
 8. The positively buoyant wave energy converter of claim 2,wherein the gas is nitrogen.
 9. The positively buoyant wave energyconverter of claim 2, wherein the gas is air.
 10. The positively buoyantwave energy converter of claim 2, wherein the gas is hydrogen.
 11. Thepositively buoyant wave energy converter of claim 2, further comprisingelectrolyzing equipment.
 12. The positively buoyant wave energyconverter of claim 2, further comprising a chemical fuel generator.